Aura desktop: Fix startup by setting the input method on the root window.

BUG=123160
TEST=none


Review URL: https://chromiumcodereview.appspot.com/10492011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@140366 0039d316-1c4b-4281-b951-d872f2087c98
  explicit RootWindowScreenPositionClient(aura::RootWindow* root_window)
      : root_window_(root_window) {}

  explicit RootWindowScreenPositionClient(aura::RootWindow* root_window)
      : root_window_(root_window) {}
