Export DefaultXKeysymFromHardwarekeycode.

This function will be used in chrome/browser/chromeos/input_method to convert X key event to KeyboardCode.

BUG=326931

Review URL: https://codereview.chromium.org/99993003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241639 0039d316-1c4b-4281-b951-d872f2087c98
More TSan v2 suppressions:
 - races on callbacks in media::AesDecryptor (issue 329530)

BUG=329530
TBR=groby@chromium.org

Review URL: https://codereview.chromium.org/114343003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241640 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241640