cc: Plumbing for BeginFrameSource based on Surfaces

cc/surfaces/surface.h

 // Copyright 2014 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.
 
 #ifndef CC_SURFACES_SURFACE_H_
 #define CC_SURFACES_SURFACE_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 62 matching lines @@
     return destruction_dependencies_.size();
   }
 
   const std::vector<SurfaceId>& referenced_surfaces() const {
     return referenced_surfaces_;
   }
 
   bool destroyed() const { return destroyed_; }
   void set_destroyed(bool destroyed) { destroyed_ = destroyed; }
 
+  void AddDisplay(Display* display) {

[jbauman, 2015/09/04 23:58:36]

Probably best to use BeginFrameSource* everywhere here.

+    if (!base::ContainsValue(currently_displayed_on_,  display)) {

[jbauman, 2015/09/04 23:58:36]

DCHECK this?

+      currently_displayed_on_.push_back(display);
+      factory_->client()->SetBeginFrameSource(surface_id_, static_cast<BeginFrameSource*>(getPrimaryDisplay()));

[jbauman, 2015/09/04 23:58:36]

Be careful, as factory_ can be an invalidated weak pointer if the factory has
been destroyed.

Also, we should have factory destruction reset the BeginFrameSource for its
client.

+    }
+  }
+
+  void RemoveDisplay(Display* display) {
+    DCHECK(base::ContainsValue(current_displayed_on_,  display));
+
+    base::RemoveValue(current_displayed_on_, display);
+
+    factory_->client()->SetBeginFrameSource(surface_id_, static_cast<BeginFrameSource*>(getPrimaryDisplay()));
+  }
+
+  Display* getPrimaryDisplay() {
+    if (currently_displayed_on_.empty())
+      return NULL;
+    return current_displayed_on_[0];
+  }
+
  private:
   void ClearCopyRequests();
 
   SurfaceId surface_id_;
   base::WeakPtr<SurfaceFactory> factory_;
   // TODO(jamesr): Support multiple frames in flight.
   scoped_ptr<CompositorFrame> current_frame_;
   int frame_index_;
   bool destroyed_;
   std::vector<SurfaceSequence> destruction_dependencies_;
 
+  std::vector<Display*> currently_displayed_on_;
   std::vector<SurfaceId> referenced_surfaces_;
 
   DrawCallback draw_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(Surface);
 };
 
 }  // namespace cc
 
 #endif  // CC_SURFACES_SURFACE_H_