[Extensions] Clean up MessagingBindings

[Extensions] Clean up MessagingBindings

MessagingBindings contains the custom bindings for extension messaging,
but most of the implementation is buried in an "ExtensionImpl" class
in an anonymous namespace. Apart from being a misleading name (I think
this dates back to the chrome.extension API), this makes the code hard
to read. Since I'm making changes here for crbug.com/642380, clean up
the code here with no behavior changes.

Make MessagingBindings (which previously just had static methods)
encompass ExtensionImpl, and remove some unneeded includes.

BUG=642380
Committed: https://crrev.com/4012b3bab05e4abd00ea9e50f96807d9bb014126
Cr-Commit-Position: refs/heads/master@{#415693}

[Devlin, 2016-08-30 22:40:41]

The CQ bit was checked by rdevlin.cronin@chromium.org to run a CQ dry run

[Devlin, 2016-08-30 22:40:55]

rdevlin.cronin@chromium.org changed reviewers:
+ lazyboy@chromium.org

[Devlin, 2016-08-30 22:40:56]

Istiaque, mind taking a look?  This one's just clean up - no behavior changes.

https://codereview.chromium.org/2295753003/diff/1/extensions/renderer/messagi...
File extensions/renderer/messaging_bindings.cc (left):

https://codereview.chromium.org/2295753003/diff/1/extensions/renderer/messagi...
extensions/renderer/messaging_bindings.cc:62: class ExtensionImpl : public
ObjectBackedNativeHandler {
All these are copy-pasted with no behavior changes to the MessagingBinding
methods.

[commit-bot: I haz the power, 2016-08-30 22:41:35]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-30 23:38:58]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-30 23:38:59]

Dry run: This issue passed the CQ dry run.

[lazyboy, 2016-08-31 17:40:39]

lgtm (this one slipped through).

[Devlin, 2016-08-31 18:23:48]

The CQ bit was checked by rdevlin.cronin@chromium.org

[commit-bot: I haz the power, 2016-08-31 18:25:01]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-31 18:37:03]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-08-31 18:39:51]

Description was changed from

==========
[Extensions] Clean up MessagingBindings

MessagingBindings contains the custom bindings for extension messaging,
but most of the implementation is buried in an "ExtensionImpl" class
in an anonymous namespace. Apart from being a misleading name (I think
this dates back to the chrome.extension API), this makes the code hard
to read. Since I'm making changes here for crbug.com/642380, clean up
the code here with no behavior changes.

Make MessagingBindings (which previously just had static methods)
encompass ExtensionImpl, and remove some unneeded includes.

BUG=642380
==========

to

==========
[Extensions] Clean up MessagingBindings

MessagingBindings contains the custom bindings for extension messaging,
but most of the implementation is buried in an "ExtensionImpl" class
in an anonymous namespace. Apart from being a misleading name (I think
this dates back to the chrome.extension API), this makes the code hard
to read. Since I'm making changes here for crbug.com/642380, clean up
the code here with no behavior changes.

Make MessagingBindings (which previously just had static methods)
encompass ExtensionImpl, and remove some unneeded includes.

BUG=642380

Committed: https://crrev.com/4012b3bab05e4abd00ea9e50f96807d9bb014126
Cr-Commit-Position: refs/heads/master@{#415693}
==========

[commit-bot: I haz the power, 2016-08-31 18:39:52]

Patchset 1 (id:??) landed as
https://crrev.com/4012b3bab05e4abd00ea9e50f96807d9bb014126
Cr-Commit-Position: refs/heads/master@{#415693}