Remove the 2-level input method system & InputMethodBridge.

ui/aura_extra/image_window_delegate.cc

Index: ui/aura_extra/image_window_delegate.cc
diff --git a/ui/aura_extra/image_window_delegate.cc b/ui/aura_extra/image_window_delegate.cc
index 9e4b35e679e040b22d88760541559f0478f3f606..726b8be7c8a1a06fbfffe702007b451d65ff3d7d 100644
--- a/ui/aura_extra/image_window_delegate.cc
+++ b/ui/aura_extra/image_window_delegate.cc
@@ -45,10 +45,6 @@ void ImageWindowDelegate::OnBoundsChanged(const gfx::Rect& old_bounds,
     size_mismatch_ = window_size_ != image_.AsImageSkia().size();
 }
 
-ui::TextInputClient* ImageWindowDelegate::GetFocusedTextInputClient() {
-  return nullptr;
-}
-
 gfx::NativeCursor ImageWindowDelegate::GetCursor(const gfx::Point& point) {
   return gfx::kNullCursor;
 }