Add content::RenderWidgetHost::MouseEventCallback

content/browser/renderer_host/render_widget_host_impl.cc

Index: content/browser/renderer_host/render_widget_host_impl.cc
diff --git a/content/browser/renderer_host/render_widget_host_impl.cc b/content/browser/renderer_host/render_widget_host_impl.cc
index 16892a172a0dc70dc7b0efdd81ad30eaab68d82b..ec0de420ffd150de1c52a013b620d281b2c1c41f 100644
--- a/content/browser/renderer_host/render_widget_host_impl.cc
+++ b/content/browser/renderer_host/render_widget_host_impl.cc
@@ -1016,6 +1016,12 @@ void RenderWidgetHostImpl::ForwardMouseEventWithLatencyInfo(
     const MouseEventWithLatencyInfo& mouse_event) {
   TRACE_EVENT2("input", "RenderWidgetHostImpl::ForwardMouseEvent",
                "x", mouse_event.event.x, "y", mouse_event.event.y);
+
+  // First, let mouse event callbacks take a shot at handling the event.  If a
+  // callback handles the event, it should not be propagated to the renderer.
+  if (MouseEventCallbacksHandleEvent(mouse_event.event))

[jam, 2013/08/27 16:17:53]

nit: given the size of this function, why not just inline it here? also the
comment is describing pretty simple code, so remove per style guide

[wdzierzanowski, 2013/08/27 19:29:51]

In fact, I didn't care much for this being a separate function or the comment. I
was just trying to "fit in" with similar code for the keyboard events. Anyway,
the function is now inlined and the comment is gone.

+    return;
+
   input_router_->SendMouseEvent(mouse_event);
 }
 
@@ -1134,6 +1140,21 @@ void RenderWidgetHostImpl::RemoveKeyboardListener(
   keyboard_listeners_.RemoveObserver(listener);
 }
 
+void RenderWidgetHostImpl::AddMouseEventCallback(
+    const MouseEventCallback& callback) {
+  mouse_event_callbacks_.push_back(callback);
+}
+
+void RenderWidgetHostImpl::RemoveMouseEventCallback(
+    const MouseEventCallback& callback) {
+  for (size_t i = 0; i < mouse_event_callbacks_.size(); ++i) {
+    if (mouse_event_callbacks_[i].Equals(callback)) {
+      mouse_event_callbacks_.erase(mouse_event_callbacks_.begin() + i);
+      return;
+    }
+  }
+}
+
 void RenderWidgetHostImpl::GetWebScreenInfo(WebKit::WebScreenInfo* result) {
   TRACE_EVENT0("renderer_host", "RenderWidgetHostImpl::GetWebScreenInfo");
   if (GetView())
@@ -1899,6 +1920,16 @@ bool RenderWidgetHostImpl::KeyPressListenersHandleEvent(
   return false;
 }
 
+bool RenderWidgetHostImpl::MouseEventCallbacksHandleEvent(
+    const WebMouseEvent& event) {
+  for (size_t i = 0; i < mouse_event_callbacks_.size(); ++i) {
+    if (mouse_event_callbacks_[i].Run(event))
+      return true;
+  }
+
+  return false;
+}
+
 InputEventAckState RenderWidgetHostImpl::FilterInputEvent(
     const WebKit::WebInputEvent& event, const ui::LatencyInfo& latency_info) {
   if (overscroll_controller() &&