Don't ignore synthesized mouse events for anything other than the client area or points which return HTNOWHERE as we only receive
WM_TOUCH messages for the client area.

This fixes bug https://code.google.com/p/chromium/issues/detail?id=291092 where chrome apps don't respond to touch events
on the sysmenu buttons like minimize/restore, etc as their non client view implementation expects to handle them via the
mouse click notifications.

In any case we should not be ignoring synthesized mouse messages for outside the client area as we don't receive touch messages
for the non client.

BUG=291092
R=girard@chromium.org, sky@chromium.org, sky

Review URL: https://codereview.chromium.org/23965008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@227196 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 227196