Reland r57788 - Expose Extension Bindings to Component Applications

Reland r57788 - Expose Extension Bindings to Component Applications

This patch allows component (built-in) extension apps to have extension api bindings. 

Note that this patch adds browser-side api permission checking for extension requests. 

This is step two along the path to exposing an extension management api to the gallery (webstore).

Original Review: http://codereview.chromium.org/3163044
BUG=27431
TBR=mpcomplete

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=57941