mus: Allow embedder to intercept events.

content/browser/renderer_host/render_widget_host_view_mus.h

 // Copyright 2015 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MUS_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MUS_H_
 
 #include <stddef.h>
 
 #include "base/macros.h"
 #include "build/build_config.h"
+#include "components/mus/public/cpp/input_event_handler.h"
 #include "components/mus/public/cpp/scoped_window_ptr.h"
 #include "components/mus/public/cpp/window.h"
 #include "content/browser/renderer_host/render_widget_host_view_base.h"
 #include "content/public/browser/render_process_host_observer.h"
 
 namespace content {
 
 class RenderWidgetHost;
 class RenderWidgetHostImpl;
 struct NativeWebKeyboardEvent;
 struct TextInputState;
 
 // See comments in render_widget_host_view.h about this class and its members.
 // This version of RenderWidgetHostView is for builds of Chrome that run through
 // the mojo shell and use the Mandoline UI Service (Mus). Mus is responsible for
 // windowing, compositing, and input event dispatch. The purpose of
 // RenderWidgetHostViewMus is to manage the mus::Window owned by the content
 // embedder. The browser is the owner of the mus::Window, controlling properties
 // such as visibility, and bounds. Some aspects such as input, focus, and cursor
 // are managed by Mus directly. Input event routing will be plumbed directly to
 // the renderer from Mus.
-class CONTENT_EXPORT RenderWidgetHostViewMus : public RenderWidgetHostViewBase {
+class CONTENT_EXPORT RenderWidgetHostViewMus
+    : public RenderWidgetHostViewBase,
+      NON_EXPORTED_BASE(public mus::InputEventHandler) {
  public:
   RenderWidgetHostViewMus(mus::Window* parent_window,
                           RenderWidgetHostImpl* widget);
   ~RenderWidgetHostViewMus() override;
 
  private:
   // Set the bounds of the window and handle size changes.  Assumes the caller
   // has already adjusted the origin of |rect| to conform to whatever coordinate
   // space is required by the aura::Window.
   void InternalSetBounds(const gfx::Rect& rect);
@@ skipping 63 matching lines @@
   void ShowDefinitionForSelection() override;
   bool SupportsSpeech() const override;
   void SpeakSelection() override;
   bool IsSpeaking() const override;
   void StopSpeaking() override;
 #endif  // defined(OS_MACOSX)
 
   void LockCompositingSurface() override;
   void UnlockCompositingSurface() override;
 
+  // mus::InputEventHandler:
+  void OnWindowInputEvent(
+      mus::Window* target,
+      const ui::Event& event,
+      std::unique_ptr<base::Callback<void(mus::mojom::EventResult)>>*
+          ack_callback) override;
+
   RenderWidgetHostImpl* host_;
 
   aura::Window* aura_window_;
 
   std::unique_ptr<mus::ScopedWindowPtr> mus_window_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewMus);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MUS_H_