diff --git a/core/renderers/geras/constants.js b/core/renderers/geras/constants.js
index 0272d921f..9a923a34a 100644
--- a/core/renderers/geras/constants.js
+++ b/core/renderers/geras/constants.js
@@ -11,20 +11,21 @@
  */
 'use strict';
 
-goog.provide('Blockly.geras.ConstantProvider');
+goog.module('Blockly.geras.ConstantProvider');
+goog.module.declareLegacyNamespace();
 
-goog.require('Blockly.blockRendering.ConstantProvider');
-goog.require('Blockly.utils.object');
+const BaseConstantProvider = goog.require('Blockly.blockRendering.ConstantProvider');
+const object = goog.require('Blockly.utils.object');
 
 
 /**
  * An object that provides constants for rendering blocks in Geras mode.
  * @constructor
  * @package
- * @extends {Blockly.blockRendering.ConstantProvider}
+ * @extends {BaseConstantProvider}
  */
-Blockly.geras.ConstantProvider = function() {
-  Blockly.geras.ConstantProvider.superClass_.constructor.call(this);
+const ConstantProvider = function() {
+  ConstantProvider.superClass_.constructor.call(this);
 
   /**
    * @override
@@ -47,23 +48,23 @@ Blockly.geras.ConstantProvider = function() {
    */
   this.STATEMENT_BOTTOM_SPACER = -this.NOTCH_HEIGHT / 2;
 };
-Blockly.utils.object.inherits(Blockly.geras.ConstantProvider,
-    Blockly.blockRendering.ConstantProvider);
+object.inherits(ConstantProvider, BaseConstantProvider);
 
 
 /**
  * @override
  */
-Blockly.geras.ConstantProvider.prototype.getCSS_ = function(selector) {
-  return Blockly.geras.ConstantProvider.superClass_.getCSS_.call(this, selector)
-      .concat([
-        /* eslint-disable indent */
-        // Insertion marker.
-        selector + ' .blocklyInsertionMarker>.blocklyPathLight,',
-        selector + ' .blocklyInsertionMarker>.blocklyPathDark {',
-          'fill-opacity: ' + this.INSERTION_MARKER_OPACITY + ';',
-          'stroke: none;',
-        '}',
-        /* eslint-enable indent */
-      ]);
+ConstantProvider.prototype.getCSS_ = function(selector) {
+  return ConstantProvider.superClass_.getCSS_.call(this, selector).concat([
+    /* eslint-disable indent */
+    // Insertion marker.
+    selector + ' .blocklyInsertionMarker>.blocklyPathLight,',
+    selector + ' .blocklyInsertionMarker>.blocklyPathDark {',
+      'fill-opacity: ' + this.INSERTION_MARKER_OPACITY + ';',
+      'stroke: none;',
+    '}',
+    /* eslint-enable indent */
+  ]);
 };
+
+exports = ConstantProvider;
diff --git a/tests/deps.js b/tests/deps.js
index 427b425de..95167497f 100644
--- a/tests/deps.js
+++ b/tests/deps.js
@@ -130,7 +130,7 @@ goog.addDependency('../../core/renderers/common/info.js', ['Blockly.blockRenderi
 goog.addDependency('../../core/renderers/common/marker_svg.js', ['Blockly.blockRendering.MarkerSvg'], ['Blockly.ASTNode', 'Blockly.Events', 'Blockly.Events.MarkerMove', 'Blockly.connectionTypes', 'Blockly.utils.Svg', 'Blockly.utils.dom']);
 goog.addDependency('../../core/renderers/common/path_object.js', ['Blockly.blockRendering.PathObject'], ['Blockly.blockRendering.IPathObject', 'Blockly.utils.Svg', 'Blockly.utils.dom'], {'lang': 'es6', 'module': 'goog'});
 goog.addDependency('../../core/renderers/common/renderer.js', ['Blockly.blockRendering.Renderer'], ['Blockly.IRegistrable', 'Blockly.InsertionMarkerManager', 'Blockly.blockRendering.ConstantProvider', 'Blockly.blockRendering.Debug', 'Blockly.blockRendering.Drawer', 'Blockly.blockRendering.IPathObject', 'Blockly.blockRendering.MarkerSvg', 'Blockly.blockRendering.PathObject', 'Blockly.blockRendering.RenderInfo', 'Blockly.connectionTypes']);
-goog.addDependency('../../core/renderers/geras/constants.js', ['Blockly.geras.ConstantProvider'], ['Blockly.blockRendering.ConstantProvider', 'Blockly.utils.object'], {'lang': 'es5'});
+goog.addDependency('../../core/renderers/geras/constants.js', ['Blockly.geras.ConstantProvider'], ['Blockly.blockRendering.ConstantProvider', 'Blockly.utils.object'], {'lang': 'es6', 'module': 'goog'});
 goog.addDependency('../../core/renderers/geras/drawer.js', ['Blockly.geras.Drawer'], ['Blockly.blockRendering.Drawer', 'Blockly.geras.Highlighter', 'Blockly.geras.RenderInfo', 'Blockly.utils.object', 'Blockly.utils.svgPaths']);
 goog.addDependency('../../core/renderers/geras/highlight_constants.js', ['Blockly.geras.HighlightConstantProvider'], ['Blockly.blockRendering.ConstantProvider', 'Blockly.utils.svgPaths'], {'lang': 'es5'});
 goog.addDependency('../../core/renderers/geras/highlighter.js', ['Blockly.geras.Highlighter'], ['Blockly.blockRendering.Types', 'Blockly.utils.svgPaths']);