Remove disabled tests.

The tests for same functionality have been checked by
TextInput_TextInputStateChangedTest even it is only for Aura configuration.
The disabled tests are not for Aura/Chrome OS but real expectation is platform
independent. So now safely remove these tests.

BUG=151798
TEST=try bots

Review URL: https://codereview.chromium.org/25834002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@231016 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 231016