mus: Allow embedder to intercept events.

content/browser/renderer_host/render_widget_host_view_mus.cc

Index: content/browser/renderer_host/render_widget_host_view_mus.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_mus.cc b/content/browser/renderer_host/render_widget_host_view_mus.cc
index d2d7b7c1f71e7aab1285b84e8b4de5ff23e78ea1..624c26a70e15be272a55f8dc0d8f95f233fcf906 100644
--- a/content/browser/renderer_host/render_widget_host_view_mus.cc
+++ b/content/browser/renderer_host/render_widget_host_view_mus.cc
@@ -7,8 +7,11 @@
 #include <utility>
 
 #include "build/build_config.h"
+#include "components/mus/public/cpp/property_type_converters.h"
 #include "components/mus/public/cpp/window.h"
+#include "components/mus/public/cpp/window_property.h"
 #include "components/mus/public/cpp/window_tree_client.h"
+#include "components/mus/public/interfaces/window_manager_constants.mojom.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/common/render_widget_window_tree_client_factory.mojom.h"
@@ -32,6 +35,7 @@ RenderWidgetHostViewMus::RenderWidgetHostViewMus(mus::Window* parent_window,
   mus::Window* window = parent_window->window_tree()->NewWindow();
   window->SetVisible(true);
   window->SetBounds(gfx::Rect(300, 300));
+  window->set_input_event_handler(this);
   parent_window->AddChild(window);
   mus_window_.reset(new mus::ScopedWindowPtr(window));
   host_->SetView(this);
@@ -44,7 +48,8 @@ RenderWidgetHostViewMus::RenderWidgetHostViewMus(mus::Window* parent_window,
   mus::mojom::WindowTreeClientPtr window_tree_client;
   factory->CreateWindowTreeClientForRenderWidget(
       host_->GetRoutingID(), mojo::GetProxy(&window_tree_client));
-  mus_window_->window()->Embed(std::move(window_tree_client));
+  mus_window_->window()->Embed(std::move(window_tree_client),
+                               mus::mojom::kEmbedFlagEmbedderInterceptsEvents);
 }
 
 RenderWidgetHostViewMus::~RenderWidgetHostViewMus() {}
@@ -298,4 +303,12 @@ void RenderWidgetHostViewMus::UnlockCompositingSurface() {
   NOTIMPLEMENTED();
 }
 
+void RenderWidgetHostViewMus::OnWindowInputEvent(
+    mus::Window* window,
+    const ui::Event& event,
+    std::unique_ptr<base::Callback<void(mus::mojom::EventResult)>>*
+        ack_callback) {
+  // TODO(sad): Dispatch |event| to the RenderWidgetHost.
+}
+
 }  // namespace content