Gets events dispatching working in mushrome

ui/aura/mus/window_tree_client.cc

Index: ui/aura/mus/window_tree_client.cc
diff --git a/ui/aura/mus/window_tree_client.cc b/ui/aura/mus/window_tree_client.cc
index 6609d5390926a9659bd315cbf384311c78ab7ec9..90573b1a8b3865925cb9790e1e4f175a1a9f288f 100644
--- a/ui/aura/mus/window_tree_client.cc
+++ b/ui/aura/mus/window_tree_client.cc
@@ -278,8 +278,9 @@ void WindowTreeClient::ConnectViaWindowTreeFactory() {
   SetWindowTree(std::move(window_tree));
 }
 
-void WindowTreeClient::ConnectAsWindowManager() {
+void WindowTreeClient::ConnectAsWindowManager(bool dispatch_from_host) {
   DCHECK(window_manager_delegate_);
+  dispatch_from_host_ = dispatch_from_host;
 
   ui::mojom::WindowManagerWindowTreeFactoryPtr factory;
   connector_->BindInterface(ui::mojom::kServiceName, &factory);
@@ -1252,7 +1253,16 @@ void WindowTreeClient::OnWindowInputEvent(uint32_t 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.
   std::unique_ptr<ui::Event> mapped_event = MapEvent(*event.get());
-  DispatchEventToTarget(mapped_event.get(), window);
+  if (dispatch_from_host_ && mapped_event->IsLocatedEvent()) {
+    gfx::Point host_location = mapped_event->AsLocatedEvent()->location();
+    aura::Window::ConvertPointToTarget(window->GetWindow(),
+                                       window->GetWindow()->GetHost()->window(),
+                                       &host_location);
+    mapped_event->AsLocatedEvent()->set_location(host_location);
+    GetWindowTreeHostMus(window)->SendEventToSink(mapped_event.get());
+  } else {
+    DispatchEventToTarget(mapped_event.get(), window);
+  }
   ack_handler.set_handled(mapped_event->handled());
 }