Cleanup and comments

core/field.js

@@ -136,9 +136,12 @@ Blockly.Field.BORDER_RECT_DEFAULT_HEIGHT = 16;
  */
 Blockly.Field.TEXT_DEFAULT_HEIGHT = 12.5;
 
-Blockly.Field.WIDTH_PADDING = 10;
-
-Blockly.Field.HEIGHT_PADDING = 10;
+/**
+ * The padding added to the width by the border rect, if it exists.
+ * @type {number}
+ * @package
+ */
+Blockly.Field.X_PADDING = 10;
 
 /**
  * Name of field.  Unique within each block.
@@ -297,11 +300,13 @@ Blockly.Field.prototype.initView = function() {
 Blockly.Field.prototype.createBorderRect_ = function() {
   this.size_.height =
       Math.max(this.size_.height, Blockly.Field.BORDER_RECT_DEFAULT_HEIGHT);
+  this.size_.width =
+      Math.max(this.size_.width, Blockly.Field.X_PADDING);
   this.borderRect_ = Blockly.utils.dom.createSvgElement('rect',
       {
         'rx': 4,
         'ry': 4,
-        'x': -Blockly.Field.WIDTH_PADDING / 2,
+        'x': -Blockly.Field.X_PADDING / 2,
         'y': 0,
         'height': this.size_.height,
         'width': this.size_.width
@@ -318,7 +323,7 @@ Blockly.Field.prototype.createTextElement_ = function() {
   this.textElement_ = Blockly.utils.dom.createSvgElement('text',
       {
         'class': 'blocklyText',
-        // This may just be trying to vertically center the text?
+        // The y position is the baseline of the text.
         'y': Blockly.Field.TEXT_DEFAULT_HEIGHT,
         'x': 0
       }, this.fieldGroup_);
@@ -587,7 +592,7 @@ Blockly.Field.prototype.updateSize_ = function() {
   var textWidth = Blockly.Field.getCachedWidth(this.textElement_);
   var totalWidth = textWidth;
   if (this.borderRect_) {
-    totalWidth += Blockly.Field.WIDTH_PADDING;
+    totalWidth += Blockly.Field.X_PADDING;
     this.borderRect_.setAttribute('width', totalWidth);
   }
   this.size_.width = totalWidth;

core/field_colour.js

@@ -78,7 +78,7 @@ Blockly.FieldColour.fromJson = function(options) {
  * @private
  * @const
  */
-Blockly.FieldColour.DEFAULT_WIDTH = 16 + Blockly.Field.WIDTH_PADDING;
+Blockly.FieldColour.DEFAULT_WIDTH = 16 + Blockly.Field.X_PADDING;
 
 /**
  * Default height of a colour field.

core/field_dropdown.js

@@ -99,9 +99,11 @@ Blockly.FieldDropdown.CHECKMARK_OVERHANG = 25;
 Blockly.FieldDropdown.MAX_MENU_HEIGHT_VH = 0.45;
 
 /**
- * Used to position the imageElement_ correctly.
+ * The y offset from the top of the field to the top of the image, if an image
+ * is selected.
  * @type {number}
  * @const
+ * @private
  */
 Blockly.FieldDropdown.IMAGE_Y_OFFSET = 5;
 
@@ -109,6 +111,7 @@ Blockly.FieldDropdown.IMAGE_Y_OFFSET = 5;
  * The total vertical padding above and below an image.
  * @type {number}
  * @const
+ * @private
  */
 Blockly.FieldDropdown.IMAGE_Y_PADDING = Blockly.FieldDropdown.IMAGE_Y_OFFSET * 2;
 
@@ -160,8 +163,6 @@ Blockly.FieldDropdown.prototype.initView = function() {
   } else {
     this.textElement_.appendChild(this.arrow_);
   }
-
-  this.contentDimensions_ = new Blockly.utils.Size(0, 0);
 };
 
 /**
@@ -493,11 +494,12 @@ Blockly.FieldDropdown.prototype.renderSelectedImage_ = function() {
 
   var arrowWidth = Blockly.Field.getCachedWidth(this.arrow_);
 
-  // Height and width include the border rect.
   var imageHeight = Number(this.imageJson_.height);
   var imageWidth = Number(this.imageJson_.width);
+
+  // Height and width include the border rect.
   this.size_.height = imageHeight + Blockly.FieldDropdown.IMAGE_Y_PADDING;
-  this.size_.width = imageWidth + arrowWidth + Blockly.Field.WIDTH_PADDING;
+  this.size_.width = imageWidth + arrowWidth + Blockly.Field.X_PADDING;
 
   if (this.sourceBlock_.RTL) {
     this.imageElement_.setAttribute('x', arrowWidth);
@@ -519,7 +521,7 @@ Blockly.FieldDropdown.prototype.renderSelectedText_ = function() {
   // 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.WIDTH_PADDING;
+      Blockly.Field.getCachedWidth(this.textElement_) + Blockly.Field.X_PADDING;
 };
 
 /**

core/field_image.js

@@ -65,6 +65,7 @@ Blockly.FieldImage = function(src, width, height,
     throw Error('Height and width values of an image field must be greater' +
       ' than 0.');
   }
+  // Store the image height, since it is different from the field height.
   this.imageHeight_ = imageHeight;
   this.size_ = new Blockly.utils.Size(imageWidth,
       imageHeight + Blockly.FieldImage.Y_PADDING);
@@ -115,6 +116,12 @@ Blockly.FieldImage.prototype.EDITABLE = false;
  */
 Blockly.FieldImage.prototype.isDirty_ = false;
 
+/**
+ * Vertical padding below the image, which is included in the reported height of
+ * the field.
+ * @type {number}
+ * @private
+ */
 Blockly.FieldImage.Y_PADDING = 1;
 
 /**