diff --git a/content/canvas/src/CustomQS_Canvas.h b/content/canvas/src/CustomQS_Canvas.h
new file mode 100644
index 000000000000..731b3032279e
--- /dev/null
+++ b/content/canvas/src/CustomQS_Canvas.h
@@ -0,0 +1,52 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef CustomQS_Canvas_h
+#define CustomQS_Canvas_h
+
+#include "jsapi.h"
+
+static bool
+GetPositiveInt(JSContext* cx, JSObject& obj, const char* name, uint32_t* out)
+{
+  JS::Value temp;
+  int32_t signedInt;
+  if (!JS_GetProperty(cx, &obj, name, &temp) ||
+      !JS_ValueToECMAInt32(cx, temp, &signedInt)) {
+    return false;
+  }
+  if (signedInt <= 0) {
+    return xpc_qsThrow(cx, NS_ERROR_DOM_TYPE_MISMATCH_ERR);
+  }
+  *out = uint32_t(signedInt);
+  return true;
+}
+
+static bool
+GetImageData(JSContext* cx, const JS::Value& imageData,
+             uint32_t* width, uint32_t* height, JS::Anchor<JSObject*>* array)
+{
+  if (!imageData.isObject()) {
+    return xpc_qsThrow(cx, NS_ERROR_DOM_TYPE_MISMATCH_ERR);
+  }
+
+  JSObject& dataObject = imageData.toObject();
+
+  if (!GetPositiveInt(cx, dataObject, "width", width) ||
+      !GetPositiveInt(cx, dataObject, "height", height)) {
+    return false;
+  }
+
+  JS::Value temp;
+  if (!JS_GetProperty(cx, &dataObject, "data", &temp)) {
+    return false;
+  }
+  if (!temp.isObject()) {
+    return xpc_qsThrow(cx, NS_ERROR_DOM_TYPE_MISMATCH_ERR);
+  }
+  array->set(&temp.toObject());
+  return true;
+}
+
+#endif // CustomQS_Canvas_h
diff --git a/content/canvas/src/CustomQS_Canvas2D.h b/content/canvas/src/CustomQS_Canvas2D.h
index d935457b3e96..89cd4d012d8d 100644
--- a/content/canvas/src/CustomQS_Canvas2D.h
+++ b/content/canvas/src/CustomQS_Canvas2D.h
@@ -42,6 +42,7 @@
 #include "nsIDOMCanvasRenderingContext2D.h"
 #include "CheckedInt.h"
 #include "nsMathUtils.h"
+#include "CustomQS_Canvas.h"
 
 #include "jsapi.h"
 
@@ -219,32 +220,6 @@ CreateImageData(JSContext* cx,
     return true;
 }
 
-static bool
-GetImageDataDimensions(JSContext *cx, JSObject *dataObject, uint32_t *width, uint32_t *height)
-{
-    jsval temp;
-    int32_t wi, hi;
-    
-    // Need to check that dataObject is ImageData object. That's hard for the moment 
-    // because they're just vanilla objects in our implementation.
-    // Let's guess, if the object has valid width and height then it's suitable
-    // for this operation.
-    if (!JS_GetProperty(cx, dataObject, "width", &temp) ||
-        !JS_ValueToECMAInt32(cx, temp, &wi))
-        return false;
-
-    if (!JS_GetProperty(cx, dataObject, "height", &temp) ||
-        !JS_ValueToECMAInt32(cx, temp, &hi))
-        return false;
-
-    if (wi <= 0 || hi <= 0)
-        return xpc_qsThrow(cx, NS_ERROR_DOM_INDEX_SIZE_ERR);
-
-    *width = uint32_t(wi);
-    *height = uint32_t(hi);
-    return true;
-}
-
 static JSBool
 nsIDOMCanvasRenderingContext2D_CreateImageData(JSContext *cx, unsigned argc, jsval *vp)
 {
@@ -258,16 +233,11 @@ nsIDOMCanvasRenderingContext2D_CreateImageData(JSContext *cx, unsigned argc, jsv
     jsval *argv = JS_ARGV(cx, vp);
 
     if (argc == 1) {
-        // The specification asks to throw NOT_SUPPORTED if first argument is NULL,
-        // An object is expected, so throw an exception for all primitives.
-        if (JSVAL_IS_PRIMITIVE(argv[0]))
-            return xpc_qsThrow(cx, NS_ERROR_DOM_NOT_SUPPORTED_ERR);
-
-        JSObject *dataObject = JSVAL_TO_OBJECT(argv[0]);
-
         uint32_t data_width, data_height;
-        if (!GetImageDataDimensions(cx, dataObject, &data_width, &data_height))
+        JS::Anchor<JSObject*> darray;
+        if (!GetImageData(cx, argv[0], &data_width, &data_height, &darray)) {
             return false;
+        }
 
         return CreateImageData(cx, data_width, data_height, NULL, 0, 0, vp);
     }
@@ -370,10 +340,11 @@ nsIDOMCanvasRenderingContext2D_PutImageData(JSContext *cx, unsigned argc, jsval
 
     jsval *argv = JS_ARGV(cx, vp);
 
-    if (JSVAL_IS_PRIMITIVE(argv[0]))
-        return xpc_qsThrow(cx, NS_ERROR_DOM_TYPE_MISMATCH_ERR);
-
-    JSObject *dataObject = JSVAL_TO_OBJECT(argv[0]);
+    uint32_t w, h;
+    JS::Anchor<JSObject*> darray;
+    if (!GetImageData(cx, argv[0], &w, &h, &darray)) {
+        return false;
+    }
 
     double xd, yd;
     if (!JS_ValueToNumber(cx, argv[1], &xd) ||
@@ -388,13 +359,6 @@ nsIDOMCanvasRenderingContext2D_PutImageData(JSContext *cx, unsigned argc, jsval
     int32_t x = JS_DoubleToInt32(xd);
     int32_t y = JS_DoubleToInt32(yd);
 
-    // Grab width, height, and the dense array from the dataObject.
-    JS::AutoValueRooter tv(cx);
-
-    uint32_t w, h;
-    if (!GetImageDataDimensions(cx, dataObject, &w, &h))
-        return JS_FALSE;
-
     // the optional dirty rect
     bool hasDirtyRect = false;
     int32_t dirtyX = 0,
@@ -424,24 +388,16 @@ nsIDOMCanvasRenderingContext2D_PutImageData(JSContext *cx, unsigned argc, jsval
         hasDirtyRect = true;
     }
 
-    if (!JS_GetProperty(cx, dataObject, "data", tv.jsval_addr()))
-        return JS_FALSE;
-
-    if (JSVAL_IS_PRIMITIVE(tv.jsval_value()))
-        return xpc_qsThrow(cx, NS_ERROR_DOM_TYPE_MISMATCH_ERR);
-
-    JSObject *darray = JSVAL_TO_OBJECT(tv.jsval_value());
-
     JS::AutoValueRooter tsrc_tvr(cx);
 
     JSObject *tsrc = NULL;
-    if (js::GetObjectClass(darray) == &js::TypedArray::fastClasses[js::TypedArray::TYPE_UINT8] ||
-        js::GetObjectClass(darray) == &js::TypedArray::fastClasses[js::TypedArray::TYPE_UINT8_CLAMPED])
+    if (js::GetObjectClass(darray.get()) == &js::TypedArray::fastClasses[js::TypedArray::TYPE_UINT8] ||
+        js::GetObjectClass(darray.get()) == &js::TypedArray::fastClasses[js::TypedArray::TYPE_UINT8_CLAMPED])
     {
-        tsrc = js::TypedArray::getTypedArray(darray);
-    } else if (JS_IsArrayObject(cx, darray) || js_IsTypedArray(darray)) {
+        tsrc = darray.get();
+    } else if (JS_IsArrayObject(cx, darray.get()) || js_IsTypedArray(darray.get())) {
         // ugh, this isn't a uint8 typed array, someone made their own object; convert it to a typed array
-        JSObject *nobj = js_CreateTypedArrayWithArray(cx, js::TypedArray::TYPE_UINT8, darray);
+        JSObject *nobj = js_CreateTypedArrayWithArray(cx, js::TypedArray::TYPE_UINT8, darray.get());
         if (!nobj)
             return JS_FALSE;
 
diff --git a/content/canvas/src/CustomQS_WebGL.h b/content/canvas/src/CustomQS_WebGL.h
index 6d21d6e08a43..9a88e035a18a 100644
--- a/content/canvas/src/CustomQS_WebGL.h
+++ b/content/canvas/src/CustomQS_WebGL.h
@@ -42,6 +42,7 @@
 
 #include "jsapi.h"
 #include "jstypedarray.h"
+#include "CustomQS_Canvas.h"
 
 #define GET_INT32_ARG(var, index) \
   int32_t var; \
@@ -479,33 +480,16 @@ TexImage2DImageDataOrElement(JSContext* cx, T& self, JS::Value* object)
 
     // Failed to interpret object as an Element, now try to interpret it as
     // ImageData.
-    JSObject* imageData = &object->toObject();
-
-    jsval js_width, js_height, js_data;
-    if (!JS_GetProperty(cx, imageData, "width", &js_width) ||
-        !JS_GetProperty(cx, imageData, "height", &js_height) ||
-        !JS_GetProperty(cx, imageData, "data", &js_data)) {
+    uint32_t int_width, int_height;
+    JS::Anchor<JSObject*> obj_data;
+    if (!GetImageData(cx, *object, &int_width, &int_height, &obj_data)) {
         return false;
     }
-    if (js_width  == JSVAL_VOID ||
-        js_height == JSVAL_VOID ||
-        !js_data.isObject())
-    {
-        return xpc_qsThrow(cx, NS_ERROR_FAILURE);
-    }
-    int32_t int_width, int_height;
-    JSObject *obj_data = JSVAL_TO_OBJECT(js_data);
-    if (!JS_ValueToECMAInt32(cx, js_width, &int_width) ||
-        !JS_ValueToECMAInt32(cx, js_height, &int_height))
-    {
-        return false;
-    }
-    if (!js_IsTypedArray(obj_data))
-    {
+    if (!js_IsTypedArray(obj_data.get())) {
         return xpc_qsThrow(cx, NS_ERROR_FAILURE);
     }
 
-    nsresult rv = self.DoCallForImageData(int_width, int_height, obj_data);
+    nsresult rv = self.DoCallForImageData(int_width, int_height, obj_data.get());
     return NS_SUCCEEDED(rv) || xpc_qsThrow(cx, rv);
 }
 
diff --git a/content/canvas/src/Makefile.in b/content/canvas/src/Makefile.in
index 61c751271125..97388e6c53d2 100644
--- a/content/canvas/src/Makefile.in
+++ b/content/canvas/src/Makefile.in
@@ -49,6 +49,7 @@ LIBRARY_NAME	= gkconcvs_s
 LIBXUL_LIBRARY  = 1
 
 EXPORTS = \
+	CustomQS_Canvas.h \
 	CustomQS_Canvas2D.h \
 	CustomQS_WebGL.h \
 	$(NULL)
diff --git a/content/canvas/test/test_canvas.html b/content/canvas/test/test_canvas.html
index 6df50da8110e..45eb618aed51 100644
--- a/content/canvas/test/test_canvas.html
+++ b/content/canvas/test/test_canvas.html
@@ -7681,7 +7681,7 @@ var _thrown = undefined; try {
 <!-- [[[ test_2d.imageData.create1.zero.html ]]] -->
 
 <p>Canvas test: 2d.imageData.create1.zero - bug 630040</p>
-<!-- Testing: createImageData(null) throws NOT_SUPPORTED_ERR -->
+<!-- Testing: createImageData(null) throws TypeError -->
 <canvas id="c262a" width="100" height="50"><p class="fallback">FAIL (fallback content)</p></canvas>
 <script>
 
@@ -7692,7 +7692,7 @@ var ctx = canvas.getContext('2d');
 
 var _thrown = undefined; try {
   ctx.createImageData(null);
-} catch (e) { _thrown = e }; ok(_thrown && _thrown.code == DOMException.NOT_SUPPORTED_ERR, "should throw NOT_SUPPORTED_ERR");
+} catch (e) { _thrown = e }; todo(_thrown && _thrown instanceof TypeError, "should throw TypeError");
 
 
 }
@@ -10790,7 +10790,7 @@ if (ctx.createImageData) {
 } catch (e) { _thrown = e }; todo(_thrown && _thrown.code == DOMException.NOT_SUPPORTED_ERR, "should throw NOT_SUPPORTED_ERR");
     var _thrown = undefined; try {
   ctx.createImageData(1);
-} catch (e) { _thrown = e }; ok(_thrown && _thrown.code == DOMException.NOT_SUPPORTED_ERR, "should throw NOT_SUPPORTED_ERR");
+} catch (e) { _thrown = e }; todo(_thrown && _thrown.code == DOMException.NOT_SUPPORTED_ERR, "should throw NOT_SUPPORTED_ERR");
 }
 if (ctx.getImageData) {
     var _thrown = undefined; try {