Don't request wheel or touch events when the view of pepper has no area.

content/renderer/pepper/pepper_plugin_instance_impl.cc

Index: content/renderer/pepper/pepper_plugin_instance_impl.cc
diff --git a/content/renderer/pepper/pepper_plugin_instance_impl.cc b/content/renderer/pepper/pepper_plugin_instance_impl.cc
index c80fe6bd5639e7f1ad68d5478054d3717d3e748e..9657823ce8b66f7cd3c08018e3d1cbd686d94c1c 100644
--- a/content/renderer/pepper/pepper_plugin_instance_impl.cc
+++ b/content/renderer/pepper/pepper_plugin_instance_impl.cc
@@ -1292,6 +1292,11 @@ void PepperPluginInstanceImpl::ViewChanged(
   view_data_.scroll_offset = PP_MakePoint(scroll_offset.width(),
                                           scroll_offset.height());
 
+  // The view size may have changed and we might need to update
+  // our registration of event listeners.
+  UpdateTouchEventRequest();
+  container_->setWantsWheelEvents(IsAcceptingWheelEvents());

[bbudge, 2016/12/02 18:38:01]

Would you consider refactoring IsAcceptingWheelEvents into
UpdateWheelEventRequest to match how touch events work? It seems to be doing the
same thing.

[dtapuska, 2016/12/02 19:42:08]

Done.

+
   if (desired_fullscreen_state_ || view_data_.is_fullscreen) {
     bool is_fullscreen_element = container_->isFullscreenElement();
     if (!view_data_.is_fullscreen && desired_fullscreen_state_ &&
@@ -1635,6 +1640,12 @@ void PepperPluginInstanceImpl::SendFocusChangeNotification() {
 }
 
 void PepperPluginInstanceImpl::UpdateTouchEventRequest() {
+  // If the view has 0 area don't request touch events.
+  if (view_data_.rect.size.width == 0 || view_data_.rect.size.height == 0) {

[bbudge, 2016/12/02 18:38:01]

Could you use unobscured_rect_.IsEmpty() here instead? I think that might be
better, if I understand the purpose of this change, which is to not request
events that we can never receive. I'm assuming it's impossible for Blink to
return touch events when the plugin is obscured.

https://cs.chromium.org/chromium/src/content/renderer/pepper/pepper_plugin_in...

[dtapuska, 2016/12/02 19:42:07]

Although that may be optimal I'd worry that it would cause more work. Since if
we adjust when setWantsWheelEvents(...) it ends up telling the scroll
co-ordinator to update geometry. see;
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/web/WebPluginC...

The minimal thing I am after is fixing 0,0 width/height flash plugins asking to
listen to input which is un-necessary

[bbudge, 2016/12/02 22:10:29]

OK

+    container_->requestTouchEventType(
+        blink::WebPluginContainer::TouchEventRequestTypeNone);
+    return;
+  }
   bool raw_touch = (filtered_input_event_mask_ & PP_INPUTEVENT_CLASS_TOUCH) ||
                    (input_event_mask_ & PP_INPUTEVENT_CLASS_TOUCH);
   container_->requestTouchEventType(
@@ -1644,6 +1655,10 @@ void PepperPluginInstanceImpl::UpdateTouchEventRequest() {
 }
 
 bool PepperPluginInstanceImpl::IsAcceptingWheelEvents() const {
+  // If the view has 0 area don't request wheel events.
+  if (view_data_.rect.size.width == 0 || view_data_.rect.size.height == 0)
+    return false;
+
   return (filtered_input_event_mask_ & PP_INPUTEVENT_CLASS_WHEEL) ||
          (input_event_mask_ & PP_INPUTEVENT_CLASS_WHEEL);
 }