Create only a single LegacyRenderWidgetHostHWND per WebContentsViewAura.

content/browser/renderer_host/render_widget_host_view_aura.h

 // Copyright (c) 2012 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_AURA_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_AURA_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 208 matching lines @@
   gfx::NativeViewAccessible AccessibilityGetNativeViewAccessible() override;
   void ShowDisambiguationPopup(const gfx::Rect& rect_pixels,
                                const SkBitmap& zoomed_bitmap) override;
   bool LockMouse() override;
   void UnlockMouse() override;
   void OnSwapCompositorFrame(uint32 output_surface_id,
                              scoped_ptr<cc::CompositorFrame> frame) override;
   void DidStopFlinging() override;
 
 #if defined(OS_WIN)
+  void SetLegacyRenderWidgetHostHWND(LegacyRenderWidgetHostHWND* legacy_hwnd);
   virtual void SetParentNativeViewAccessible(
       gfx::NativeViewAccessible accessible_parent) override;
   virtual gfx::NativeViewId GetParentForWindowlessPlugin() const override;
 #endif
 
   // Overridden from ui::TextInputClient:
   void SetCompositionText(const ui::CompositionText& composition) override;
   void ConfirmCompositionText() override;
   void ClearCompositionText() override;
   void InsertText(const base::string16& text) override;
@@ skipping 79 matching lines @@
   void OnTextInputStateChanged(const ViewHostMsg_TextInputState_Params& params);
 
 #if defined(OS_WIN)
   // Sets the cutout rects from constrained windows. These are rectangles that
   // windowed NPAPI plugins shouldn't paint in. Overwrites any previous cutout
   // rects.
   void UpdateConstrainedWindowRects(const std::vector<gfx::Rect>& rects);
 
   // Updates the cursor clip region. Used for mouse locking.
   void UpdateMouseLockRegion();
-
-  // Notification that the LegacyRenderWidgetHostHWND was destroyed.
-  void OnLegacyWindowDestroyed();
 #endif
 
   void DisambiguationPopupRendered(bool success, const SkBitmap& result);
 
   void HideDisambiguationPopup();
 
   void ProcessDisambiguationGesture(ui::GestureEvent* event);
 
   void ProcessDisambiguationMouse(ui::MouseEvent* event);
 
@@ skipping 246 matching lines @@
   // Contains information about each windowed plugin's clip and cutout rects (
   // from the renderer). This is needed because when the transient windows
   // over this view changes, we need this information in order to create a new
   // region for the HWND.
   PluginWindowMoves plugin_window_moves_;
 
   // The LegacyRenderWidgetHostHWND class provides a dummy HWND which is used
   // for accessibility, as the container for windowless plugins like
   // Flash/Silverlight, etc and for legacy drivers for trackpoints/trackpads,
   // etc.
-  // The LegacyRenderWidgetHostHWND instance is created during the first call
-  // to RenderWidgetHostViewAura::InternalSetBounds. The instance is destroyed
-  // when the LegacyRenderWidgetHostHWND hwnd is destroyed.
   content::LegacyRenderWidgetHostHWND* legacy_render_widget_host_HWND_;
-
-  // Set to true if the legacy_render_widget_host_HWND_ instance was destroyed
-  // by Windows. This could happen if the browser window was destroyed by
-  // DestroyWindow for e.g. This flag helps ensure that we don't try to create
-  // the LegacyRenderWidgetHostHWND instance again as that would be a futile
-  // exercise.
-  bool legacy_window_destroyed_;
 #endif
 
   bool has_snapped_to_boundary_;
 
   TouchEditingClient* touch_editing_client_;
 
   scoped_ptr<OverscrollController> overscroll_controller_;
 
   // The last scroll offset of the view.
   gfx::Vector2dF last_scroll_offset_;
@@ skipping 16 matching lines @@
   // view, so we can ensure the window hasn't moved between copying from the
   // compositing surface and showing the disambiguation popup.
   gfx::Vector2dF disambiguation_scroll_offset_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAura);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_AURA_H_