chromeos: Remove some IME methods from ash::SystemTrayDelegate
For the mustash project we're trying to eliminate delegates that call
from ash back into chrome browser.
The IME InputMethodManager interfaces live in //ui/base/ime/chromeos, and
//ash already uses them, so convert some of the system tray code to use
InputMethodManager directly.
* Remove InputMethodSwitchRecorder and move histogram recording to //ash
* Use InputMethodManager directly in the ash keyboard accelerator code
* Remove ash::ImeControlDelegate and chrome's ImeController.
* Use MockInputMethodManager in all AcceleratorControllerTests
BUG=724305
TEST=ash_unittests, manually switch IMEs when running chrome
Review-Url: https://codereview.chromium.org/2891263002
Cr-Commit-Position: refs/heads/master@{#474380}
21 files changed
