Change ImageElement to use onLoad.listen instead of on.load and

Change ImageElement to use onLoad.listen instead of on.load and 
adjust event dispatch accordingly.
Committed: https://code.google.com/p/dart/source/detail?r=19883

[vsm, 2013-03-08 17:49:35]

lgtm

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
File runtime/embedders/openglui/common/gl.dart (right):

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:70: class EventTarget extends Object {
Nit: Don't need "extends Object".

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:75: var event_listeners =
listeners[event.type];
event_listeners -> eventListeners per style guide

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:76: for (var i = 0; i <
event_listeners.length; i++) {
Just iterate directly:
for (var eventListener in eventListeners) { ... }

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:121: Map<EventTarget, Map<String,
List<Function>>> _listeners = new Map();
Function -> EventListener ?

This might also be cleaner if you just have a Map<String, List<EventListener>>
defined in EventTarget instead of a global map.

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:256: // with more granularity; right
now we just iterate through DOM nodes which should
line len

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:257: // just be the one canvas.
Should the code assert that there is just one canvas?

[gram, 2013-03-11 21:25:08]

PTAL. I moved _listeners into EventTarget per your suggestion which caused a bit
of churn.

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
File runtime/embedders/openglui/common/gl.dart (right):

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:70: class EventTarget extends Object {
On 2013/03/08 17:49:35, vsm wrote:
> Nit: Don't need "extends Object".

Done.

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:76: for (var i = 0; i <
event_listeners.length; i++) {
On 2013/03/08 17:49:35, vsm wrote:
> Just iterate directly:
> for (var eventListener in eventListeners) { ... }

Will do, but is there a perf implication? I know that in many languages this
creates an Iterator object that is much more costly than just using an int
index.

The other reason I did this is that we can have null entries in the list; I
don't expect that should be a problem but wanted to be cautious.

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:121: Map<EventTarget, Map<String,
List<Function>>> _listeners = new Map();
On 2013/03/08 17:49:35, vsm wrote:
> Function -> EventListener ?
> 
> This might also be cleaner if you just have a Map<String, List<EventListener>>
> defined in EventTarget instead of a global map.

Done.

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:256: // with more granularity; right
now we just iterate through DOM nodes which should
On 2013/03/08 17:49:35, vsm wrote:
> line len

Done.

https://codereview.chromium.org/12428011/diff/1/runtime/embedders/openglui/co...
runtime/embedders/openglui/common/gl.dart:257: // just be the one canvas.
On 2013/03/08 17:49:35, vsm wrote:
> Should the code assert that there is just one canvas?

Done.

[vsm, 2013-03-12 17:26:18]

lgtm

https://chromiumcodereview.appspot.com/12428011/diff/5001/runtime/embedders/o...
File runtime/embedders/openglui/common/gl.dart (right):

https://chromiumcodereview.appspot.com/12428011/diff/5001/runtime/embedders/o...
runtime/embedders/openglui/common/gl.dart:73: static Map<EventTarget,
Map<String, List<EventListener>>> _listeners = new Map();
nit: length

[gram, 2013-03-12 17:47:14]

https://chromiumcodereview.appspot.com/12428011/diff/5001/runtime/embedders/o...
File runtime/embedders/openglui/common/gl.dart (right):

https://chromiumcodereview.appspot.com/12428011/diff/5001/runtime/embedders/o...
runtime/embedders/openglui/common/gl.dart:73: static Map<EventTarget,
Map<String, List<EventListener>>> _listeners = new Map();
On 2013/03/12 17:26:18, vsm wrote:
> nit: length

Done.

[gram, 2013-03-12 17:47:43]

Committed patchset #3 manually as r19883 (presubmit successful).