Re-work MaterialComponent

Re-work MaterialComponent

Instead of MaterialComponent being a base class, components that want material
behavior simply create a MaterialComponent during their render function. This
approach gives the component more flexibility as to its structure and gives
MaterialComponent more flexibility has to how the components it generates are
related to the existing children.

Also, I've improved some of the event delegation code. There's no reason to
attach event handlers to the root component you emit during |render| because
the framework already delegates events from your root component to you.

R=rafaelw@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/ea80070ae03f2b0ec666f0663ff84d1500a2b53d

[rafaelw, 2015-03-06 21:02:13]

rafaelw@chromium.org changed reviewers:
+ rafaelw@chromium.org

[rafaelw, 2015-03-06 21:02:14]

lgtm w/ question. I like this approach.

https://codereview.chromium.org/983903003/diff/1/sky/framework/fn.dart
File sky/framework/fn.dart (right):

https://codereview.chromium.org/983903003/diff/1/sky/framework/fn.dart#newcod...
sky/framework/fn.dart:261: if (this == oldElement)
How can this happen?

[abarth-chromium, 2015-03-06 21:37:01]

https://codereview.chromium.org/983903003/diff/1/sky/framework/fn.dart
File sky/framework/fn.dart (right):

https://codereview.chromium.org/983903003/diff/1/sky/framework/fn.dart#newcod...
sky/framework/fn.dart:261: if (this == oldElement)
On 2015/03/06 at 21:02:14, rafaelw wrote:
> How can this happen?

I should build a reduced test case.  It happens with this patch if you click a
stockrow.  It's possible the correct fix is elsewhere.

[abarth-chromium, 2015-03-11 17:17:57]

Committed patchset #2 (id:20001) manually as
ea80070ae03f2b0ec666f0663ff84d1500a2b53d (presubmit successful).