Perform direct routing of mouse events when the pointer is locked.

content/browser/renderer_host/render_widget_host_delegate.h

Index: content/browser/renderer_host/render_widget_host_delegate.h
diff --git a/content/browser/renderer_host/render_widget_host_delegate.h b/content/browser/renderer_host/render_widget_host_delegate.h
index 8319bc6534d81d61f0055fb7f4d962d27db6c705..3c1d35c460f263aa39e6a5fdb274275cfa31b894 100644
--- a/content/browser/renderer_host/render_widget_host_delegate.h
+++ b/content/browser/renderer_host/render_widget_host_delegate.h
@@ -183,6 +183,10 @@ class CONTENT_EXPORT RenderWidgetHostDelegate {
   // Returns true if |render_widget_host| holds the mouse lock.
   virtual bool HasMouseLock(RenderWidgetHostImpl* render_widget_host);
 
+  // Returns the widget that holds the mouse lock or nullptr if the mouse isn't
+  // locked.
+  virtual RenderWidgetHostImpl* MouseLockWidget();
+
   // Called when the widget has sent a compositor proto.  This is used in Btlimp
   // mode with the RemoteChannel compositor.
   virtual void ForwardCompositorProto(RenderWidgetHostImpl* render_widget_host,