aura: Unify WindowTreeHost for some platforms

ui/aura/window_tree_host.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/aura/window_tree_host.h"
 
 #include "base/thread_task_runner_handle.h"
 #include "base/trace_event/trace_event.h"
 #include "ui/aura/client/capture_client.h"
 #include "ui/aura/client/cursor_client.h"
@@ skipping 31 matching lines @@
 // WindowTreeHost, public:
 
 WindowTreeHost::~WindowTreeHost() {
   DCHECK(!compositor_) << "compositor must be destroyed before root window";
   if (owned_input_method_) {
     delete input_method_;
     input_method_ = nullptr;
   }
 }
 
-#if defined(OS_ANDROID)
-// static
-WindowTreeHost* WindowTreeHost::Create(const gfx::Rect& bounds) {
-  // This is only hit for tests and ash, right now these aren't an issue so
-  // adding the CHECK.
-  // TODO(sky): decide if we want a factory.
-  CHECK(false);
-  return nullptr;
-}
-#endif
-
 // static
 WindowTreeHost* WindowTreeHost::GetForAcceleratedWidget(
     gfx::AcceleratedWidget widget) {
   return reinterpret_cast<WindowTreeHost*>(
       ui::ViewProp::GetValue(widget, kWindowTreeHostForAcceleratedWidget));
 }
 
 void WindowTreeHost::InitHost() {
   InitCompositor();
   UpdateRootWindowSize(GetBounds().size());
@@ skipping 238 matching lines @@
   client::CursorClient* cursor_client = client::GetCursorClient(window());
   if (cursor_client) {
     const gfx::Display& display =
         gfx::Screen::GetScreenFor(window())->GetDisplayNearestWindow(window());
     cursor_client->SetDisplay(display);
   }
   dispatcher()->OnCursorMovedToRootLocation(root_location);
 }
 
 }  // namespace aura