diff --git a/core/block.js b/core/block.js
index eeb4a0c48..43fe84f8d 100644
--- a/core/block.js
+++ b/core/block.js
@@ -39,6 +39,7 @@ goog.require('Blockly.Input');
 goog.require('Blockly.Mutator');
 goog.require('Blockly.utils');
 goog.require('Blockly.utils.Coordinate');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.string');
 goog.require('Blockly.Warning');
 goog.require('Blockly.Workspace');
@@ -1636,18 +1637,13 @@ Blockly.Block.prototype.interpolate_ = function(message, args, lastDummyAlign) {
             default:
               // This should handle all field JSON parsing, including
               // options that can be applied to any field type.
-              field = Blockly.Field.fromJson(element);
+              field = Blockly.utils.fields.fromJson(element);
 
               // Unknown field.
               if (!field) {
                 if (element['alt']) {
                   element = element['alt'];
                   altRepeat = true;
-                } else {
-                  console.warn('Blockly could not create a field of type ' +
-                      element['type'] +
-                      '. You may need to register your custom field.  See ' +
-                      'github.com/google/blockly/issues/1584');
                 }
               }
           }
diff --git a/core/block_dragger.js b/core/block_dragger.js
index fa6bc723d..7e64b8e8e 100644
--- a/core/block_dragger.js
+++ b/core/block_dragger.js
@@ -31,6 +31,7 @@ goog.require('Blockly.Events');
 goog.require('Blockly.Events.BlockMove');
 goog.require('Blockly.InsertionMarkerManager');
 goog.require('Blockly.utils.Coordinate');
+goog.require('Blockly.utils.dom');
 
 
 /**
@@ -164,7 +165,7 @@ Blockly.BlockDragger.prototype.startBlockDrag = function(currentDragDeltaXY,
 
   // During a drag there may be a lot of rerenders, but not field changes.
   // Turn the cache on so we don't do spurious remeasures during the drag.
-  Blockly.Field.startCache();
+  Blockly.utils.dom.startTextWidthCache();
   this.workspace_.setResizesEnabled(false);
   Blockly.blockAnimations.disconnectUiStop();
 
@@ -225,7 +226,7 @@ Blockly.BlockDragger.prototype.endBlockDrag = function(e, currentDragDeltaXY) {
   this.dragBlock(e, currentDragDeltaXY);
   this.dragIconData_ = [];
 
-  Blockly.Field.stopCache();
+  Blockly.utils.dom.stopTextWidthCache();
 
   Blockly.blockAnimations.disconnectUiStop();
 
diff --git a/core/block_svg.js b/core/block_svg.js
index 9db42e1b6..4c22e0fbe 100644
--- a/core/block_svg.js
+++ b/core/block_svg.js
@@ -270,9 +270,9 @@ Blockly.BlockSvg.prototype.setParent = function(newParent) {
     return;
   }
 
-  Blockly.Field.startCache();
+  Blockly.utils.dom.startTextWidthCache();
   Blockly.BlockSvg.superClass_.setParent.call(this, newParent);
-  Blockly.Field.stopCache();
+  Blockly.utils.dom.stopTextWidthCache();
 
   var svgRoot = this.getSvgRoot();
 
@@ -893,7 +893,7 @@ Blockly.BlockSvg.prototype.dispose = function(healStack, animate) {
     return;
   }
   Blockly.Tooltip.hide();
-  Blockly.Field.startCache();
+  Blockly.utils.dom.startTextWidthCache();
   // Save the block's workspace temporarily so we can resize the
   // contents once the block is disposed.
   var blockWorkspace = this.workspace;
@@ -952,7 +952,7 @@ Blockly.BlockSvg.prototype.dispose = function(healStack, animate) {
   this.svgPath_ = null;
   this.svgPathLight_ = null;
   this.svgPathDark_ = null;
-  Blockly.Field.stopCache();
+  Blockly.utils.dom.stopTextWidthCache();
 };
 
 /**
@@ -1539,7 +1539,7 @@ Blockly.BlockSvg.prototype.positionNearConnection = function(sourceConnection,
  *   If true, also render block's parent, grandparent, etc.  Defaults to true.
  */
 Blockly.BlockSvg.prototype.render = function(opt_bubble) {
-  Blockly.Field.startCache();
+  Blockly.utils.dom.startTextWidthCache();
   this.rendered = true;
   // TODO (#2702): Choose an API for picking the renderer.
   Blockly.blockRendering.render(this);
@@ -1555,7 +1555,7 @@ Blockly.BlockSvg.prototype.render = function(opt_bubble) {
       this.workspace.resizeContents();
     }
   }
-  Blockly.Field.stopCache();
+  Blockly.utils.dom.stopTextWidthCache();
 };
 
 /**
diff --git a/core/field.js b/core/field.js
index ff34e0baa..54554129a 100644
--- a/core/field.js
+++ b/core/field.js
@@ -57,71 +57,6 @@ Blockly.Field = function(value, opt_validator) {
   opt_validator && this.setValidator(opt_validator);
 };
 
-/**
- * The set of all registered fields, keyed by field type as used in the JSON
- * definition of a block.
- * @type {!Object<string, !{fromJson: Function}>}
- * @private
- */
-Blockly.Field.TYPE_MAP_ = {};
-
-/**
- * Registers a field type. May also override an existing field type.
- * Blockly.Field.fromJson uses this registry to find the appropriate field.
- * @param {string} type The field type name as used in the JSON definition.
- * @param {!{fromJson: Function}} fieldClass The field class containing a
- *     fromJson function that can construct an instance of the field.
- * @throws {Error} if the type name is empty, or the fieldClass is not an
- *     object containing a fromJson function.
- */
-Blockly.Field.register = function(type, fieldClass) {
-  if ((typeof type != 'string') || (type.trim() == '')) {
-    throw Error('Invalid field type "' + type + '"');
-  }
-  if (!fieldClass || (typeof fieldClass.fromJson != 'function')) {
-    throw Error('Field "' + fieldClass + '" must have a fromJson function');
-  }
-  Blockly.Field.TYPE_MAP_[type] = fieldClass;
-};
-
-/**
- * Construct a Field from a JSON arg object.
- * Finds the appropriate registered field by the type name as registered using
- * Blockly.Field.register.
- * @param {!Object} options A JSON object with a type and options specific
- *     to the field type.
- * @return {Blockly.Field} The new field instance or null if a field wasn't
- *     found with the given type name
- * @package
- */
-Blockly.Field.fromJson = function(options) {
-  var fieldClass = Blockly.Field.TYPE_MAP_[options['type']];
-  if (fieldClass) {
-    var field = fieldClass.fromJson(options);
-    if (options['tooltip'] !== undefined) {
-      var rawValue = options['tooltip'];
-      var localizedText = Blockly.utils.replaceMessageReferences(rawValue);
-      field.setTooltip(localizedText);
-    }
-    return field;
-  }
-  return null;
-};
-
-/**
- * Temporary cache of text widths.
- * @type {Object}
- * @private
- */
-Blockly.Field.cacheWidths_ = null;
-
-/**
- * Number of current references to cache.
- * @type {number}
- * @private
- */
-Blockly.Field.cacheReference_ = 0;
-
 /**
  * The default height of the border rect on any field.
  * @type {number}
@@ -588,14 +523,14 @@ Blockly.Field.prototype.render_ = function() {
 /**
  * Updates the width of the field. Redirects to updateSize_().
  * @deprecated May 2019  Use Blockly.Field.updateSize_() to force an update
- * to the size of the field, or Blockly.Field.getCachedWidth() to check the
- * size of the field..
+ * to the size of the field, or Blockly.utils.dom.getTextWidth() to
+ * check the size of the field.
  */
 Blockly.Field.prototype.updateWidth = function() {
   console.warn('Deprecated call to updateWidth, call' +
     ' Blockly.Field.updateSize_ to force an update to the size of the' +
-    ' field, or Blockly.Field.getCachedWidth() to check the size of the' +
-    ' field.');
+    ' field, or Blockly.utils.dom.getTextWidth() to check the size' +
+    ' of the field.');
   this.updateSize_();
 };
 
@@ -604,7 +539,7 @@ Blockly.Field.prototype.updateWidth = function() {
  * @protected
  */
 Blockly.Field.prototype.updateSize_ = function() {
-  var textWidth = Blockly.Field.getCachedWidth(this.textElement_);
+  var textWidth = Blockly.utils.dom.getTextWidth(this.textElement_);
   var totalWidth = textWidth;
   if (this.borderRect_) {
     totalWidth += Blockly.Field.X_PADDING;
@@ -613,67 +548,6 @@ Blockly.Field.prototype.updateSize_ = function() {
   this.size_.width = totalWidth;
 };
 
-/**
- * Gets the width of a text element, caching it in the process.
- * @param {!Element} textElement An SVG 'text' element.
- * @return {number} Width of element.
- */
-Blockly.Field.getCachedWidth = function(textElement) {
-  var key = textElement.textContent + '\n' + textElement.className.baseVal;
-  var width;
-
-  // Return the cached width if it exists.
-  if (Blockly.Field.cacheWidths_) {
-    width = Blockly.Field.cacheWidths_[key];
-    if (width) {
-      return width;
-    }
-  }
-
-  // Attempt to compute fetch the width of the SVG text element.
-  try {
-    if (Blockly.utils.userAgent.IE || Blockly.utils.userAgent.EDGE) {
-      width = textElement.getBBox().width;
-    } else {
-      width = textElement.getComputedTextLength();
-    }
-  } catch (e) {
-    // In other cases where we fail to geth the computed text. Instead, use an
-    // approximation and do not cache the result. At some later point in time
-    // when the block is inserted into the visible DOM, this method will be
-    // called again and, at that point in time, will not throw an exception.
-    return textElement.textContent.length * 8;
-  }
-
-  // Cache the computed width and return.
-  if (Blockly.Field.cacheWidths_) {
-    Blockly.Field.cacheWidths_[key] = width;
-  }
-  return width;
-};
-
-/**
- * Start caching field widths.  Every call to this function MUST also call
- * stopCache.  Caches must not survive between execution threads.
- */
-Blockly.Field.startCache = function() {
-  Blockly.Field.cacheReference_++;
-  if (!Blockly.Field.cacheWidths_) {
-    Blockly.Field.cacheWidths_ = {};
-  }
-};
-
-/**
- * Stop caching field widths.  Unless caching was already on when the
- * corresponding call to startCache was made.
- */
-Blockly.Field.stopCache = function() {
-  Blockly.Field.cacheReference_--;
-  if (!Blockly.Field.cacheReference_) {
-    Blockly.Field.cacheWidths_ = null;
-  }
-};
-
 /**
  * Returns the height and width of the field.
  *
diff --git a/core/field_angle.js b/core/field_angle.js
index f4871ba7b..aeb91e536 100644
--- a/core/field_angle.js
+++ b/core/field_angle.js
@@ -29,6 +29,7 @@ goog.provide('Blockly.FieldAngle');
 goog.require('Blockly.DropDownDiv');
 goog.require('Blockly.FieldTextInput');
 goog.require('Blockly.utils.dom');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.math');
 goog.require('Blockly.utils.userAgent');
 
@@ -353,4 +354,4 @@ Blockly.FieldAngle.prototype.doClassValidation_ = function(opt_newValue) {
   return n;
 };
 
-Blockly.Field.register('field_angle', Blockly.FieldAngle);
+Blockly.utils.fields.register('field_angle', Blockly.FieldAngle);
diff --git a/core/field_checkbox.js b/core/field_checkbox.js
index f75f0a800..b8f9f1d82 100644
--- a/core/field_checkbox.js
+++ b/core/field_checkbox.js
@@ -30,6 +30,7 @@ goog.require('Blockly.Events');
 goog.require('Blockly.Events.BlockChange');
 goog.require('Blockly.Field');
 goog.require('Blockly.utils.dom');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.Size');
 
 
@@ -210,4 +211,4 @@ Blockly.FieldCheckbox.prototype.convertValueToBool_ = function(value) {
   }
 };
 
-Blockly.Field.register('field_checkbox', Blockly.FieldCheckbox);
+Blockly.utils.fields.register('field_checkbox', Blockly.FieldCheckbox);
diff --git a/core/field_colour.js b/core/field_colour.js
index 2b5c529d2..13eff115e 100644
--- a/core/field_colour.js
+++ b/core/field_colour.js
@@ -31,6 +31,7 @@ goog.require('Blockly.Events');
 goog.require('Blockly.Events.BlockChange');
 goog.require('Blockly.Field');
 goog.require('Blockly.utils.colour');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.Size');
 
 
@@ -346,4 +347,4 @@ Blockly.FieldColour.prototype.dropdownDispose_ = function() {
   Blockly.unbindEvent_(this.onUpWrapper_);
 };
 
-Blockly.Field.register('field_colour', Blockly.FieldColour);
+Blockly.utils.fields.register('field_colour', Blockly.FieldColour);
diff --git a/core/field_date.js b/core/field_date.js
index d742b30f4..9b2ab30f4 100644
--- a/core/field_date.js
+++ b/core/field_date.js
@@ -29,6 +29,7 @@ goog.provide('Blockly.FieldDate');
 goog.require('Blockly.Events');
 goog.require('Blockly.Field');
 goog.require('Blockly.utils.dom');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.string');
 
 goog.require('goog.date');
@@ -323,4 +324,4 @@ Blockly.FieldDate.CSS = [
   '}'
 ];
 
-Blockly.Field.register('field_date', Blockly.FieldDate);
+Blockly.utils.fields.register('field_date', Blockly.FieldDate);
diff --git a/core/field_dropdown.js b/core/field_dropdown.js
index 210e424ca..9d481bde4 100644
--- a/core/field_dropdown.js
+++ b/core/field_dropdown.js
@@ -33,6 +33,7 @@ goog.require('Blockly.Events.BlockChange');
 goog.require('Blockly.Field');
 goog.require('Blockly.utils');
 goog.require('Blockly.utils.dom');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.Size');
 goog.require('Blockly.utils.string');
 goog.require('Blockly.utils.uiMenu');
@@ -492,7 +493,7 @@ Blockly.FieldDropdown.prototype.renderSelectedImage_ = function() {
   this.imageElement_.setAttribute('height', this.imageJson_.height);
   this.imageElement_.setAttribute('width', this.imageJson_.width);
 
-  var arrowWidth = Blockly.Field.getCachedWidth(this.arrow_);
+  var arrowWidth = Blockly.utils.dom.getTextWidth(this.arrow_);
 
   var imageHeight = Number(this.imageJson_.height);
   var imageWidth = Number(this.imageJson_.width);
@@ -524,8 +525,8 @@ Blockly.FieldDropdown.prototype.renderSelectedText_ = function() {
   this.textElement_.setAttribute('x', Blockly.Field.DEFAULT_TEXT_OFFSET);
   // Height and width include the border rect.
   this.size_.height = Blockly.Field.BORDER_RECT_DEFAULT_HEIGHT;
-  this.size_.width =
-      Blockly.Field.getCachedWidth(this.textElement_) + Blockly.Field.X_PADDING;
+  this.size_.width = Blockly.utils.dom.getTextWidth(this.textElement_)
+      + Blockly.Field.X_PADDING;
 };
 
 /**
@@ -565,4 +566,4 @@ Blockly.FieldDropdown.validateOptions_ = function(options) {
   }
 };
 
-Blockly.Field.register('field_dropdown', Blockly.FieldDropdown);
+Blockly.utils.fields.register('field_dropdown', Blockly.FieldDropdown);
diff --git a/core/field_image.js b/core/field_image.js
index b0a13ec0c..37dbf5765 100644
--- a/core/field_image.js
+++ b/core/field_image.js
@@ -30,6 +30,7 @@ goog.require('Blockly.Field');
 goog.require('Blockly.Tooltip');
 goog.require('Blockly.utils');
 goog.require('Blockly.utils.dom');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.Size');
 
 
@@ -222,4 +223,4 @@ Blockly.FieldImage.prototype.setOnClickHandler = function(func) {
   this.clickHandler_ = func;
 };
 
-Blockly.Field.register('field_image', Blockly.FieldImage);
+Blockly.utils.fields.register('field_image', Blockly.FieldImage);
diff --git a/core/field_label.js b/core/field_label.js
index abfe0b438..8134feb09 100644
--- a/core/field_label.js
+++ b/core/field_label.js
@@ -31,6 +31,7 @@ goog.require('Blockly.Field');
 goog.require('Blockly.Tooltip');
 goog.require('Blockly.utils');
 goog.require('Blockly.utils.dom');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.Size');
 
 
@@ -100,4 +101,4 @@ Blockly.FieldLabel.prototype.doClassValidation_ = function(opt_newValue) {
   return String(opt_newValue);
 };
 
-Blockly.Field.register('field_label', Blockly.FieldLabel);
+Blockly.utils.fields.register('field_label', Blockly.FieldLabel);
diff --git a/core/field_label_serializable.js b/core/field_label_serializable.js
index 833a4c61d..38f8ddb05 100644
--- a/core/field_label_serializable.js
+++ b/core/field_label_serializable.js
@@ -29,6 +29,7 @@ goog.provide('Blockly.FieldLabelSerializable');
 
 goog.require('Blockly.FieldLabel');
 goog.require('Blockly.utils');
+goog.require('Blockly.utils.fields');
 
 
 /**
@@ -75,5 +76,5 @@ Blockly.FieldLabelSerializable.prototype.EDITABLE = false;
  */
 Blockly.FieldLabelSerializable.prototype.SERIALIZABLE = true;
 
-Blockly.Field.register(
+Blockly.utils.fields.register(
     'field_label_serializable', Blockly.FieldLabelSerializable);
diff --git a/core/field_number.js b/core/field_number.js
index d430145c8..347ae60d7 100644
--- a/core/field_number.js
+++ b/core/field_number.js
@@ -27,6 +27,7 @@
 goog.provide('Blockly.FieldNumber');
 
 goog.require('Blockly.FieldTextInput');
+goog.require('Blockly.utils.fields');
 
 
 /**
@@ -138,4 +139,4 @@ Blockly.FieldNumber.prototype.doClassValidation_ = function(opt_newValue) {
   return n;
 };
 
-Blockly.Field.register('field_number', Blockly.FieldNumber);
+Blockly.utils.fields.register('field_number', Blockly.FieldNumber);
diff --git a/core/field_textinput.js b/core/field_textinput.js
index 92dcc31a0..f9fa93f25 100644
--- a/core/field_textinput.js
+++ b/core/field_textinput.js
@@ -34,6 +34,7 @@ goog.require('Blockly.utils');
 goog.require('Blockly.utils.aria');
 goog.require('Blockly.utils.Coordinate');
 goog.require('Blockly.utils.dom');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.Size');
 goog.require('Blockly.utils.userAgent');
 
@@ -448,4 +449,4 @@ Blockly.FieldTextInput.nonnegativeIntegerValidator = function(text) {
   return n;
 };
 
-Blockly.Field.register('field_input', Blockly.FieldTextInput);
+Blockly.utils.fields.register('field_input', Blockly.FieldTextInput);
diff --git a/core/field_variable.js b/core/field_variable.js
index 209d9be57..c4af8fb0d 100644
--- a/core/field_variable.js
+++ b/core/field_variable.js
@@ -31,6 +31,7 @@ goog.require('Blockly.Events.BlockChange');
 goog.require('Blockly.FieldDropdown');
 goog.require('Blockly.Msg');
 goog.require('Blockly.utils');
+goog.require('Blockly.utils.fields');
 goog.require('Blockly.utils.Size');
 goog.require('Blockly.VariableModel');
 goog.require('Blockly.Variables');
@@ -430,4 +431,4 @@ Blockly.FieldVariable.prototype.referencesVariables = function() {
   return true;
 };
 
-Blockly.Field.register('field_variable', Blockly.FieldVariable);
+Blockly.utils.fields.register('field_variable', Blockly.FieldVariable);
diff --git a/core/flyout_button.js b/core/flyout_button.js
index bf4ae27ec..973e3a320 100644
--- a/core/flyout_button.js
+++ b/core/flyout_button.js
@@ -156,7 +156,7 @@ Blockly.FlyoutButton.prototype.createDom = function() {
       this.svgGroup_);
   svgText.textContent = Blockly.utils.replaceMessageReferences(this.text_);
 
-  this.width = Blockly.Field.getCachedWidth(svgText);
+  this.width = Blockly.utils.dom.getTextWidth(svgText);
   this.height = 20;  // Can't compute it :(
 
   if (!this.isLabel_) {
diff --git a/core/utils/dom.js b/core/utils/dom.js
index 9897fb5da..694cdd9a2 100644
--- a/core/utils/dom.js
+++ b/core/utils/dom.js
@@ -63,6 +63,20 @@ Blockly.utils.dom.Node = {
   DOCUMENT_POSITION_CONTAINED_BY: 16
 };
 
+/**
+ * Temporary cache of text widths.
+ * @type {Object}
+ * @private
+ */
+Blockly.utils.dom.cacheWidths_ = null;
+
+/**
+ * Number of current references to cache.
+ * @type {number}
+ * @private
+ */
+Blockly.utils.dom.cacheReference_ = 0;
+
 /**
  * Helper method for creating SVG elements.
  * @param {string} name Element's tag name.
@@ -197,3 +211,64 @@ Blockly.utils.dom.setCssTransform = function(element, transform) {
   element.style['transform'] = transform;
   element.style['-webkit-transform'] = transform;
 };
+
+/**
+ * Start caching text widths. Every call to this function MUST also call
+ * stopTextWidthCache. Caches must not survive between execution threads.
+ */
+Blockly.utils.dom.startTextWidthCache = function() {
+  Blockly.utils.dom.cacheReference_++;
+  if (!Blockly.utils.dom.cacheWidths_) {
+    Blockly.utils.dom.cacheWidths_ = {};
+  }
+};
+
+/**
+ * Stop caching field widths. Unless caching was already on when the
+ * corresponding call to startTextWidthCache was made.
+ */
+Blockly.utils.dom.stopTextWidthCache = function() {
+  Blockly.utils.dom.cacheReference_--;
+  if (!Blockly.utils.dom.cacheReference_) {
+    Blockly.utils.dom.cacheWidths_ = null;
+  }
+};
+
+/**
+ * Gets the width of a text element, caching it in the process.
+ * @param {!Element} textElement An SVG 'text' element.
+ * @return {number} Width of element.
+ */
+Blockly.utils.dom.getTextWidth = function(textElement) {
+  var key = textElement.textContent + '\n' + textElement.className.baseVal;
+  var width;
+
+  // Return the cached width if it exists.
+  if (Blockly.utils.dom.cacheWidths_) {
+    width = Blockly.utils.dom.cacheWidths_[key];
+    if (width) {
+      return width;
+    }
+  }
+
+  // Attempt to compute fetch the width of the SVG text element.
+  try {
+    if (Blockly.utils.userAgent.IE || Blockly.utils.userAgent.EDGE) {
+      width = textElement.getBBox().width;
+    } else {
+      width = textElement.getComputedTextLength();
+    }
+  } catch (e) {
+    // In other cases where we fail to get the computed text. Instead, use an
+    // approximation and do not cache the result. At some later point in time
+    // when the block is inserted into the visible DOM, this method will be
+    // called again and, at that point in time, will not throw an exception.
+    return textElement.textContent.length * 8;
+  }
+
+  // Cache the computed width and return.
+  if (Blockly.utils.dom.cacheWidths_) {
+    Blockly.utils.dom.cacheWidths_[key] = width;
+  }
+  return width;
+};
diff --git a/core/utils/field.js b/core/utils/field.js
new file mode 100644
index 000000000..2b95cf2f8
--- /dev/null
+++ b/core/utils/field.js
@@ -0,0 +1,92 @@
+/**
+ * @license
+ * Visual Blocks Editor
+ *
+ * Copyright 2019 Google Inc.
+ * https://developers.google.com/blockly/
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// TODO: Files in this directory seem to not be specific to Blockly, yet
+//  this one is. Should it be moved to the core?
+/**
+ * @fileoverview Utility methods for handling fields.
+ * @author bekawestberg@gmail.com (Beka Westberg)
+ */
+'use strict';
+
+/**
+ * @name Blockly.utils
+ * @namespace
+ */
+goog.provide('Blockly.utils.fields');
+
+
+/**
+ * The set of all registered fields, keyed by field type as used in the JSON
+ * definition of a block.
+ * @type {!Object<string, !{fromJson: Function}>}
+ * @private
+ */
+Blockly.utils.fields.typeMap_ = {};
+
+/**
+ * Registers a field type. May also override an existing field type.
+ * Blockly.utils.fields.fromJson uses this registry to
+ * find the appropriate field type.
+ * @param {string} type The field type name as used in the JSON definition.
+ * @param {!{fromJson: Function}} fieldClass The field class containing a
+ *     fromJson function that can construct an instance of the field.
+ * @throws {Error} if the type name is empty, or the fieldClass is not an
+ *     object containing a fromJson function.
+ */
+Blockly.utils.fields.register = function(type, fieldClass) {
+  if ((typeof type != 'string') || (type.trim() == '')) {
+    throw Error('Invalid field type "' + type + '"');
+  }
+  if (!fieldClass || (typeof fieldClass.fromJson != 'function')) {
+    throw Error('Field "' + fieldClass + '" must have a fromJson function');
+  }
+  Blockly.utils.fields.typeMap_[type] = fieldClass;
+};
+
+/**
+ * Construct a Field from a JSON arg object.
+ * Finds the appropriate registered field by the type name as registered using
+ * Blockly.utils.fields.register.
+ * @param {!Object} options A JSON object with a type and options specific
+ *     to the field type.
+ * @return {Blockly.Field} The new field instance or null if a field wasn't
+ *     found with the given type name
+ * @package
+ */
+Blockly.utils.fields.fromJson = function(options) {
+  var fieldClass = Blockly.utils.fields.typeMap_[options['type']];
+  if (!fieldClass) {
+    console.warn('Blockly could not create a field of type ' + options['type'] +
+      '. The field is probably not being registered. This may be because the' +
+      ' file is not loaded, the field does not register itself (See:' +
+      ' github.com/google/blockly/issues/1584), or the registration is not' +
+      ' being reached.');
+    return null;
+  }
+
+  var field = fieldClass.fromJson(options);
+  if (options['tooltip'] !== undefined) {
+    var rawValue = options['tooltip'];
+    var localizedText = Blockly.utils.replaceMessageReferences(rawValue);
+    field.setTooltip(localizedText);
+  }
+  return field;
+};
diff --git a/core/xml.js b/core/xml.js
index 148ca3fd2..bc0e1fc0b 100644
--- a/core/xml.js
+++ b/core/xml.js
@@ -376,7 +376,7 @@ Blockly.Xml.domToWorkspace = function(xml, workspace) {
     width = workspace.getWidth();
   }
   var newBlockIds = [];  // A list of block IDs added by this call.
-  Blockly.Field.startCache();
+  Blockly.utils.dom.startTextWidthCache();
   // Safari 7.1.3 is known to provide node lists with extra references to
   // children beyond the lists' length.  Trust the length, do not use the
   // looping pattern of checking the index for an object.
@@ -433,7 +433,7 @@ Blockly.Xml.domToWorkspace = function(xml, workspace) {
     if (!existingGroup) {
       Blockly.Events.setGroup(false);
     }
-    Blockly.Field.stopCache();
+    Blockly.utils.dom.stopTextWidthCache();
   }
   // Re-enable workspace resizing.
   if (workspace.setResizesEnabled) {
diff --git a/demos/custom-fields/field_turtle.js b/demos/custom-fields/field_turtle.js
index da49d9a1a..dc7b8c8ea 100644
--- a/demos/custom-fields/field_turtle.js
+++ b/demos/custom-fields/field_turtle.js
@@ -533,7 +533,7 @@ CustomFields.FieldTurtle.prototype.fromXml = function(fieldElement) {
 
 // Blockly needs to know the JSON name of this field. Usually this is
 // registered at the bottom of the field class.
-Blockly.Field.register('field_turtle', CustomFields.FieldTurtle);
+Blockly.utils.fields.register('field_turtle', CustomFields.FieldTurtle);
 
 // Called by initView to create all of the SVGs. This is just used to keep
 // the code more organized.
diff --git a/tests/mocha/field_test.js b/tests/mocha/field_test.js
index 5493e93e2..6d5454434 100644
--- a/tests/mocha/field_test.js
+++ b/tests/mocha/field_test.js
@@ -19,7 +19,7 @@
  */
 
 suite('Abstract Fields', function() {
-  suite.skip('Is Serializable', function() {
+  suite('Is Serializable', function() {
     // Both EDITABLE and SERIALIZABLE are default.
     function FieldDefault() {
       this.name = 'NAME';
@@ -72,7 +72,7 @@ suite('Abstract Fields', function() {
       assertEquals(true, field.isSerializable());
     });
   });
-  suite.skip('setValue', function() {
+  suite('setValue', function() {
     function addSpies(field) {
       if (!this.isSpying) {
         sinon.spy(field, 'doValueInvalid_');