Relanding http://codereview.chromium.org/1746009/show...

Relanding http://codereview.chromium.org/1746009/show
(fixed the ChromeOS build).

The app launcher now uses the location bar (instead of the autocomplete edit), so
it has "tab to search" and the icons on the left side,
Also split location_bar_view.cc so that every inner-class gets its own .h and .cc
file.

BUG=None
TEST=Make sure the location bar works as expected (tab to search, bookmark star,
page actions...).
Open the app launcher, make sure "tab to search" works as expected.
	 

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=45957