Mouse lock implementation, including the renderer side and the Windows version of the browser side.

content/renderer/render_widget.h

Index: content/renderer/render_widget.h
diff --git a/content/renderer/render_widget.h b/content/renderer/render_widget.h
index 05a7d5fcebaab2579ba321ed517f72de000ffac6..855272bfc0789289dd4747ee893f9515e27ebab0 100644
--- a/content/renderer/render_widget.h
+++ b/content/renderer/render_widget.h
@@ -42,6 +42,7 @@ class PlatformCanvas;
 }
 
 namespace WebKit {
+class WebInputEvent;
 class WebMouseEvent;
 class WebWidget;
 struct WebPopupMenuInfo;
@@ -304,6 +305,14 @@ class RenderWidget : public IPC::Channel::Listener,
   // just handled.
   virtual void DidHandleMouseEvent(const WebKit::WebMouseEvent& event) {}
 
+  // Called by OnHandleInputEvent() to notify subclasses that an mouse event is
+  // about to be handled.
+  // Returns true if no further handling is needed. In that case, the event
+  // won't be sent to WebKit or trigger DidHandleMouseEvent().
+  virtual bool BeforeHandleMouseEvent(const WebKit::WebMouseEvent& event) {

[brettw, 2011/09/14 22:17:58]

Can you implement this in the .cc file? I realize some of the other functions
aren't, but this will prevent virtual function bloat (it has to be inlined in
every file that includes it).

Can you also move this to before "DidHandleMouseEvent", and mention that
DidHandleMouseEvent will not be called if you return true.

[yzshen1, 2011/09/19 20:48:41]

Done. Thanks!

+    return false;
+  }
+
   // Routing ID that allows us to communicate to the parent browser process
   // RenderWidgetHost. When MSG_ROUTING_NONE, no messages may be sent.
   int32 routing_id_;