Files.app: Pull together the event handlers of commands.

Currently the command event handlers are registered individually.  Thus once the
event is triggered, all the command handlers are invoked.  This CL pulls the
handlers together into the one handler that calls the correct command handler.

BUG=296046
TEST=manually

Review URL: https://chromiumcodereview.appspot.com/24185003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225166 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225166
drive: Add local_id to ResourceEntry

Add local_id to ResourceEntry
Increment DB version
Remove |id| argument from ResourceMetadata::RefreshEntry
Call set_local_id when appropriate

BUG=260514
TEST=unit_tests

Review URL: https://chromiumcodereview.appspot.com/24281012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225167 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225167