Enforce constant size and device scale factor for surfaces

cc/surfaces/compositor_frame_sink_support.cc

 // Copyright 2016 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 "cc/surfaces/compositor_frame_sink_support.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "cc/output/compositor_frame.h"
@@ skipping 114 matching lines @@
     }
   }
 
   std::unique_ptr<Surface> surface;
   bool create_new_surface =
       (!current_surface_ ||
        local_surface_id != current_surface_->surface_id().local_surface_id());
   if (!create_new_surface) {
     surface = std::move(current_surface_);
   } else {
-    surface = CreateSurface(local_surface_id);
+    SurfaceId surface_id(frame_sink_id_, local_surface_id);
+    gfx::Size frame_size = frame.render_pass_list.back()->output_rect.size();
+    float device_scale_factor = frame.metadata.device_scale_factor;
+    SurfaceInfo surface_info(surface_id, device_scale_factor, frame_size);
+
+    if (!surface_info.is_valid()) {
+      TRACE_EVENT_INSTANT0("cc", "Invalid SurfaceInfo",
+                           TRACE_EVENT_SCOPE_THREAD);
+      if (current_surface_)
+        DestroyCurrentSurface();
+      ReturnedResourceArray resources;
+      TransferableResource::ReturnResources(frame.resource_list, &resources);
+      ReturnResources(resources);
+      DidReceiveCompositorFrameAck();
+      return;
+    }
+
+    surface = CreateSurface(surface_info);
   }
 
-  surface->QueueFrame(
+  bool result = surface->QueueFrame(
       std::move(frame),

[Fady Samuel, 2017/05/18 20:51:32]

Shouldn't we be returning resources here if this fails and calling
DidReceiveCompositorFrameAck? 

[Saman Sami, 2017/05/19 18:28:17]

If the client misbehaves then not really.

       base::Bind(&CompositorFrameSinkSupport::DidReceiveCompositorFrameAck,
                  weak_factory_.GetWeakPtr()),
       base::BindRepeating(&CompositorFrameSinkSupport::WillDrawSurface,
                           weak_factory_.GetWeakPtr()));
 
   if (current_surface_) {
     surface->SetPreviousFrameSurface(current_surface_.get());
     DestroyCurrentSurface();
   }
   current_surface_ = std::move(surface);
 
   // TODO(eseckler): The CompositorFrame submitted below might not be activated
   // right away b/c of surface synchronization. We should only send the
   // BeginFrameAck to DisplayScheduler when it is activated. This also means
   // that we need to stay an active BFO while a CompositorFrame is pending.
   // See https://crbug.com/703079.
   if (begin_frame_source_)
     begin_frame_source_->DidFinishFrame(this, ack);
+
+  if (!result)
+    client_->DidRejectCompositorFrame();
 }
 
 void CompositorFrameSinkSupport::UpdateSurfaceReferences(
     const SurfaceId& last_surface_id,
     const LocalSurfaceId& local_surface_id) {
   const bool surface_id_changed =
       last_surface_id.local_surface_id() != local_surface_id;
 
   // If this is a display root surface and the SurfaceId is changing, make the
   // new SurfaceId reachable from the top-level root.
@@ skipping 157 matching lines @@
     return;
 
   added_frame_observer_ = needs_begin_frame_;
   if (needs_begin_frame_)
     begin_frame_source_->AddObserver(this);
   else
     begin_frame_source_->RemoveObserver(this);
 }
 
 std::unique_ptr<Surface> CompositorFrameSinkSupport::CreateSurface(
-    const LocalSurfaceId& local_surface_id) {
+    const SurfaceInfo& surface_info) {
   seen_first_frame_activation_ = false;
-  std::unique_ptr<Surface> surface = surface_manager_->CreateSurface(
-      weak_factory_.GetWeakPtr(), local_surface_id);
-  return surface;
+  return surface_manager_->CreateSurface(weak_factory_.GetWeakPtr(),
+                                         surface_info);
 }
 
 void CompositorFrameSinkSupport::DestroyCurrentSurface() {
   surface_manager_->DestroySurface(std::move(current_surface_));
 }
 
 void CompositorFrameSinkSupport::RequestCopyOfSurface(
     std::unique_ptr<CopyOutputRequest> copy_request) {
   if (!current_surface_)
     return;
 
   DCHECK(current_surface_->compositor_frame_sink_support().get() == this);
   current_surface_->RequestCopyOfOutput(std::move(copy_request));
   surface_manager_->SurfaceModified(current_surface_->surface_id());
 }
 
 }  // namespace cc