Ensure that we don't report huge mouse movement deltas for mouse enter and leave events.

content/browser/renderer_host/render_widget_host_view_aura.h

Index: content/browser/renderer_host/render_widget_host_view_aura.h
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.h b/content/browser/renderer_host/render_widget_host_view_aura.h
index 190d5c9f8e1b71677811395019d9762d6fd7e1ee..98657c04df26e99db085784dc031503033212a70 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.h
+++ b/content/browser/renderer_host/render_widget_host_view_aura.h
@@ -424,7 +424,10 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
 
   // This method computes movementX/Y and keeps track of mouse location for
   // mouse lock on all mouse move events.
-  void ModifyEventMovementAndCoords(blink::WebMouseEvent* event);
+  // |event| contains the WebMouseEvent being modified.
+  // |ui_mouse_event| contains the mouse event received.
+  void ModifyEventMovementAndCoords(blink::WebMouseEvent* event,
+                                    ui::MouseEvent* ui_mouse_event);
 
   // Sends an IPC to the renderer process to communicate whether or not
   // the mouse cursor is visible anywhere on the screen.
@@ -686,6 +689,10 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
   int32_t last_active_widget_process_id_;
   int32_t last_active_widget_routing_id_;
 
+  // The last mouse move position. It is used as the location of subsequent
+  // mouse enter and leave events.
+  gfx::Point last_mouse_position_;
+
   base::WeakPtrFactory<RenderWidgetHostViewAura> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAura);