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

content/renderer/pepper/pepper_plugin_instance_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/pepper/pepper_plugin_instance_impl.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/bit_cast.h"
@@ skipping 1274 matching lines @@
   ConvertRectToDIP(&view_data_.clip_rect);
   view_data_.css_scale *= viewport_to_dip_scale_;
   view_data_.device_scale /= viewport_to_dip_scale_;
 
   gfx::Size scroll_offset = gfx::ScaleToRoundedSize(
       container_->document().frame()->scrollOffset(), viewport_to_dip_scale_);
 
   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_ &&
         render_frame()->GetRenderWidget()->is_fullscreen_granted() &&
         is_fullscreen_element) {
       // Entered fullscreen. Only possible via SetFullscreen().
       view_data_.is_fullscreen = true;
     } else if (view_data_.is_fullscreen && !is_fullscreen_element) {
       // Exited fullscreen. Possible via SetFullscreen() or F11/link,
       // so desired_fullscreen_state might be out-of-date.
@@ skipping 323 matching lines @@
   bool has_focus = PluginHasFocus();
   render_frame_->PepperFocusChanged(this, has_focus);
 
   // instance_interface_ may have been cleared in Delete() if the
   // PepperWebPluginImpl is destroyed.
   if (instance_interface_)
     instance_interface_->DidChangeFocus(pp_instance(), PP_FromBool(has_focus));
 }
 
 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(
       raw_touch
           ? blink::WebPluginContainer::TouchEventRequestTypeRaw
           : blink::WebPluginContainer::TouchEventRequestTypeSynthesizedMouse);
 }
 
 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);
 }
 
 void PepperPluginInstanceImpl::ScheduleAsyncDidChangeView() {
   if (view_change_weak_ptr_factory_.HasWeakPtrs())
     return;  // Already scheduled.
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&PepperPluginInstanceImpl::SendAsyncDidChangeView,
                             view_change_weak_ptr_factory_.GetWeakPtr()));
@@ skipping 1779 matching lines @@
     const cc::TextureMailbox& mailbox) const {
   auto it =
       std::find_if(texture_ref_counts_.begin(), texture_ref_counts_.end(),
                    [&mailbox](const TextureMailboxRefCount& ref_count) {
                      return ref_count.first.mailbox() == mailbox.mailbox();
                    });
   return it != texture_ref_counts_.end();
 }
 
 }  // namespace content