Fix event dispatching offset problem in the client-lib in high-dpi mode. (transform)

ui/aura/mus/window_tree_client.cc

 // Copyright 2014 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/mus/window_tree_client.h"
 
 #include <stddef.h>
 
 #include <string>
 #include <utility>
@@ skipping 1135 matching lines @@
     return;
   }
 
   WindowTreeHostMus* host = GetWindowTreeHostMus(window);
   DCHECK(host);
 
   // The location of the event is relative to |window|. As the event is handed
   // to WindowTreeHost we need it to be relative to WindowTreeHost.
   if (event->IsLocatedEvent()) {
     gfx::Point host_location = event->AsLocatedEvent()->location();
-    aura::Window::ConvertPointToTarget(window->GetWindow(), host->window(),
-                                       &host_location);
+    gfx::Transform transform;
+    window->GetWindow()->layer()->GetTargetTransformRelativeTo(
+        host->window()->layer(), &transform);
+    transform.Scale(1, ScaleFactorForDisplay(window->GetWindow()));
+    auto transformed_host_location = gfx::Point3F(gfx::PointF(host_location));
+    transform.TransformPoint(&transformed_host_location);
+    host_location = gfx::ToFlooredPoint(transformed_host_location.AsPointF());
     event->AsLocatedEvent()->set_location(host_location);
   }
 
   EventAckHandler ack_handler(CreateEventResultCallback(event_id));
   // TODO(moshayedi): crbug.com/617222. No need to convert to ui::MouseEvent or
   // ui::TouchEvent once we have proper support for pointer events.
   if (event->IsMousePointerEvent()) {
     if (event->type() == ui::ET_POINTER_WHEEL_CHANGED) {
       ui::MouseWheelEvent mapped_event(*event->AsPointerEvent());
       host->SendEventToProcessor(&mapped_event);
@@ skipping 650 matching lines @@
   return ScheduleInFlightChange(base::MakeUnique<InFlightCaptureChange>(
       this, capture_synchronizer_.get(), window));
 }
 
 uint32_t WindowTreeClient::CreateChangeIdForFocus(WindowMus* window) {
   return ScheduleInFlightChange(base::MakeUnique<InFlightFocusChange>(
       this, focus_synchronizer_.get(), window));
 }
 
 }  // namespace aura