aura: Allow delegated frames to be used by more than one impl layer.

content/browser/renderer_host/render_widget_host_view_aura.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/browser/renderer_host/render_widget_host_view_aura.h"
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_number_conversions.h"
+#include "cc/layers/delegated_frame_provider.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/output/compositor_frame_ack.h"
 #include "cc/output/copy_output_request.h"
 #include "cc/output/copy_output_result.h"
 #include "cc/resources/texture_mailbox.h"
 #include "cc/trees/layer_tree_settings.h"
 #include "content/browser/accessibility/browser_accessibility_manager.h"
 #include "content/browser/accessibility/browser_accessibility_state_impl.h"
 #include "content/browser/aura/compositor_resize_lock.h"
 #include "content/browser/gpu/compositor_util.h"
@@ skipping 1438 matching lines @@
   }
 
   if (output_surface_id != last_output_surface_id_) {
     // Resource ids are scoped by the output surface.
     // If the originating output surface doesn't match the last one, it
     // indicates the renderer's output surface may have been recreated, in which
     // case we should recreate the DelegatedRendererLayer, to avoid matching
     // resources from the old one with resources from the new one which would
     // have the same id. Changing the layer to showing painted content destroys
     // the DelegatedRendererLayer.
-    // TODO(danakj): Lose and return all resources in the delegated layer first.
     window_->layer()->SetShowPaintedContent();
+    frame_provider_ = NULL;
+
+    // TODO(danakj): Lose all resources and send them back here, such as:
+    // resource_collection_->LoseAllResources();
+    // SendReturnedDelegatedResources(last_output_surface_id_);
+
+    // Drop the cc::DelegatedFrameResourceCollection so that we will not return
+    // any resources from the old output surface with the new output surface id.
+    resource_collection_->SetClient(NULL);
+    resource_collection_ = NULL;
     last_output_surface_id_ = output_surface_id;
   }
   if (frame_size.IsEmpty()) {
-    // TODO(danakj): Return all resources in the delegated layer somehow.
+    DCHECK_EQ(0u, frame_data->resource_list.size());
     window_->layer()->SetShowPaintedContent();
   } else {
-    window_->layer()->SetDelegatedFrame(frame_data.Pass(), frame_size_in_dip);
+    if (!resource_collection_) {
+      resource_collection_ = new cc::DelegatedFrameResourceCollection;
+      resource_collection_->SetClient(this);
+    }
+    if (!frame_provider_.get() || frame_size != frame_provider_->frame_size()) {
+      frame_provider_ = new cc::DelegatedFrameProvider(
+          resource_collection_.get(), frame_data.Pass());
+      window_->layer()->SetShowDelegatedContent(frame_provider_.get(),
+                                                frame_size_in_dip);
+    } else {
+      frame_provider_->SetFrameData(frame_data.Pass());
+    }
   }
   released_front_lock_ = NULL;
   current_frame_size_ = frame_size_in_dip;
   CheckResizeLock();
 
   if (paint_observer_)
     paint_observer_->OnUpdateCompositorContent();
   window_->SchedulePaintInRect(damage_rect_in_dip);
 
   ui::Compositor* compositor = GetCompositor();
   if (!compositor) {
     SendDelegatedFrameAck(output_surface_id);
   } else {
     compositor->SetLatencyInfo(latency_info);
     AddOnCommitCallbackAndDisableLocks(
         base::Bind(&RenderWidgetHostViewAura::SendDelegatedFrameAck,
                    AsWeakPtr(),
                    output_surface_id));
   }
   DidReceiveFrameFromRenderer();
 }
 
 void RenderWidgetHostViewAura::SendDelegatedFrameAck(uint32 output_surface_id) {
   cc::CompositorFrameAck ack;
-  window_->layer()->TakeUnusedResourcesForChildCompositor(&ack.resources);
-  RenderWidgetHostImpl::SendSwapCompositorFrameAck(
-      host_->GetRoutingID(), output_surface_id,
-      host_->GetProcess()->GetID(), ack);
+  if (resource_collection_)
+    resource_collection_->TakeUnusedResourcesForChildCompositor(&ack.resources);
+  RenderWidgetHostImpl::SendSwapCompositorFrameAck(host_->GetRoutingID(),
+                                                   output_surface_id,
+                                                   host_->GetProcess()->GetID(),
+                                                   ack);
+}
+
+void RenderWidgetHostViewAura::UnusedResourcesAreAvailable() {
+  // TODO(danakj): If no ack is pending, collect and send resources now.
 }
 
 void RenderWidgetHostViewAura::SwapSoftwareFrame(
     uint32 output_surface_id,
     scoped_ptr<cc::SoftwareFrameData> frame_data,
     float frame_device_scale_factor,
     const ui::LatencyInfo& latency_info) {
   const gfx::Size& frame_size = frame_data->size;
   const gfx::Rect& damage_rect = frame_data->damage_rect;
   gfx::Size frame_size_in_dip =
@@ skipping 1658 matching lines @@
   gfx::Screen::GetScreenFor(window_)->RemoveObserver(this);
 
   // This call is usually no-op since |this| object is already removed from the
   // Aura root window and we don't have a way to get an input method object
   // associated with the window, but just in case.
   DetachFromInputMethod();
   FrameMemoryManager::GetInstance()->RemoveFrame(this);
   // The destruction of the holder may call back into the RWHVA, so do it
   // early.
   framebuffer_holder_ = NULL;
+
+  if (resource_collection_.get())
+    resource_collection_->SetClient(NULL);
 }
 
 void RenderWidgetHostViewAura::UpdateCursorIfOverSelf() {
   const gfx::Point screen_point =
       gfx::Screen::GetScreenFor(GetNativeView())->GetCursorScreenPoint();
   aura::RootWindow* root_window = window_->GetRootWindow();
   if (!root_window)
     return;
 
   gfx::Rect screen_rect = GetViewBounds();
@@ skipping 189 matching lines @@
     RenderWidgetHost* widget) {
   return new RenderWidgetHostViewAura(widget);
 }
 
 // static
 void RenderWidgetHostViewPort::GetDefaultScreenInfo(WebScreenInfo* results) {
   GetScreenInfoForWindow(results, NULL);
 }
 
 }  // namespace content