Remove WebLockOrientationCallback::ErrorType

This is deprecated and WebLockOrientationError should be used.

BUG=162827

Review URL: https://codereview.chromium.org/346543003

git-svn-id: svn://svn.chromium.org/blink/trunk@176756 bbb929c8-8fbe-4397-9dbb-9b2b20218538