Revert 240810 "Support multiple TTS voices on Windows."

Speculative revert for a problem that browser_tests can't be loaded on Windows XP.

> Support multiple TTS voices on Windows.
> 
> BUG=88059
> 
> Review URL: https://codereview.chromium.org/97793002

TBR=dmazzoni@chromium.org

Review URL: https://codereview.chromium.org/105273007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240854 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 240854