Remove _boundsCache and replace it with easier _simpleBounds flag.

src/item/Item.js

@@ -1260,8 +1260,10 @@ var Item = this.Item = Base.extend(Callback, /** @lends Item# */{
 		// bounds on items without children, as we do not receive hierarchy
 		// change notifiers from children, and walking up the parents and
 		// merging cache bounds is not expensive.
+		// Allow subclasses to define _simpleBounds if they want to share the
+		// cache across all different bound types.
 		var cache = !this._children && !matrix
-				&& (this._boundsName[name] || name);
+				&& (this._simpleBounds && 'bounds' || name);
 		if (cache && this._bounds && this._bounds[cache])
 			return this._bounds[cache];
 		var bounds = this._getBounds(name, matrix);
@@ -1281,12 +1283,6 @@ var Item = this.Item = Base.extend(Callback, /** @lends Item# */{
 		return bounds;
 	};
 }, /** @lends Item# */{
-	/**
-	 * Used internally to override caching names, so bound types can share their
-	 * cache, in case they return the same results.
-	 */
-	_boundsName: {},
-
 	/**
 	 * Internal method used in all the bounds getters. It loops through all the
 	 * children, gets their bounds and finds the bounds around all of them.

src/item/PlacedSymbol.js

@@ -95,7 +95,7 @@ var PlacedSymbol = this.PlacedSymbol = PlacedItem.extend(/** @lends PlacedSymbol
 	},
 
 	_calculateBounds: function(type, matrix) {
-		// Ask the symbol definition to calculate the bounds for us
+		// Redirect the call to the symbol definition to calculate the bounds
 		return this.symbol._definition._getBounds(type, matrix);
 	},
 

src/item/Raster.js

@@ -22,6 +22,10 @@
  * @extends PlacedItem
  */
 var Raster = this.Raster = PlacedItem.extend(/** @lends Raster# */{
+	// Raster doesn't make the distinction between the different bounds,
+	// so use the same cache for all of them
+	_simpleBounds: true,
+
 	// TODO: Implement url / type, width, height.
 	// TODO: Have PlacedSymbol & Raster inherit from a shared class?
 	// DOCS: Document Raster constructor.
@@ -381,8 +385,6 @@ var Raster = this.Raster = PlacedItem.extend(/** @lends Raster# */{
 	},
 
 	_calculateBounds: function(type, matrix) {
-		// Note: Raster doesn't make the distinction between the different
-		// bounds
 		return matrix._transformBounds(
 				new Rectangle(this._size).setCenter(0, 0));
 	},

src/text/TextItem.js

@@ -26,6 +26,10 @@
  * @extends Item
  */
 var TextItem = this.TextItem = Item.extend(/** @lends TextItem# */{
+	// TextItem doesn't make the distinction between the different bounds,
+	// so use the same cache for all of them
+	_simpleBounds: true,
+
 	initialize: function() {
 		this.base();
 		this._content = '';