Filter out IME-generated OnChar messages from getting to Chrome Frame. These generated messages do not contain a native event (since they were generated), which is what Chrome Frame would need to handle them. While this affects character messages, it does not affect accelerator key presses which are the ones Chrome Frame cares about anyway.
BUG=232037
TEST=NONE
TBR=sky
Review URL: https://chromiumcodereview.appspot.com/
13853007
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@195580 0039d316-1c4b-4281-b951-d872f2087c98