GitLab

triggered from hotdog -> Bookmarks when in Metro mode.

To perform the metrics recording, this CL includes changes
to provide a callback mechanism for the asynchronous tile
creation in metro_driver.dll to report back the result of
the use gesture to the browser process. Note that both
metro_driver.dll and chrome.dll link statically to base, so
they have distinct data segments holding UMA histograms,
hence the callback.

BUG=160840
TEST=In Windows 8 Metro Mode, Hotdog -> Bookmarks -> Pin to start page:
 - pin and cancel (escape/click/touch off popup)
 - pin and confirm
 - (when pinned) unpin and cancel
 - unpin and confirm
Above should all work (and report UMA histogram data).

Review URL: https://chromiumcodereview.appspot.com/11280112

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@170916 0039d316-1c4b-4281-b951-d872f2087c98