Revert 195143 "Prevent chrome.app JSON schema from loading on ev..."

Revert 195143 "Prevent chrome.app JSON schema from loading on ev..."

Small perf regression.

> Prevent chrome.app JSON schema from loading on every page
> 
> The app API along with app.window and app.runtime have been converted to use
> the feature system. Bindings are not added to the chrome object for unavailable
> APIs that are children of available APIs. For example, if chrome.app is
> available, we will not add lazy bindings to chrome for app.window and
> app.runtime. This eliminates the need to load the app schema, because we no
> longer need to get chrome.app to add the app.runtime and app.window bindings.
> 
> BUG=55316
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=194837
> 
> Review URL: https://chromiumcodereview.appspot.com/13604005

TBR=cduvall@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=195187

[not at google - send to devlin, 2013-04-19 14:36:56]

Committed patchset #1 manually as r195187.