Remove InputMethodTSF, TSFEventRouter, TSFTextStore, TSFBridge

My understanding is that these are now unnecessary. Hopefully I
haven't removed too much here.

TBR=ben@chromium.org
R=yukawa@chromium.org
BUG=319122, 5027, 330735

Review URL: https://codereview.chromium.org/149073009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248001 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 248001