Allow out-of-process iframes to render to compositing surfaces.

content/renderer/child_frame_compositing_helper.cc

 // 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.
 
 #include "content/renderer/child_frame_compositing_helper.h"
 
 #include "cc/blink/web_layer_impl.h"
 #include "cc/layers/delegated_frame_provider.h"
 #include "cc/layers/delegated_frame_resource_collection.h"
 #include "cc/layers/delegated_renderer_layer.h"
 #include "cc/layers/solid_color_layer.h"
+#include "cc/layers/surface_layer.h"
 #include "cc/output/context_provider.h"
 #include "cc/output/copy_output_request.h"
 #include "cc/output/copy_output_result.h"
 #include "cc/resources/single_release_callback.h"
 #include "content/common/browser_plugin/browser_plugin_messages.h"
 #include "content/common/frame_messages.h"
 #include "content/common/gpu/client/context_provider_command_buffer.h"
 #include "content/renderer/browser_plugin/browser_plugin.h"
 #include "content/renderer/browser_plugin/browser_plugin_manager.h"
 #include "content/renderer/render_frame_impl.h"
 #include "content/renderer/render_frame_proxy.h"
 #include "content/renderer/render_thread_impl.h"
 #include "skia/ext/image_operations.h"
 #include "third_party/WebKit/public/web/WebFrame.h"
 #include "third_party/WebKit/public/web/WebPluginContainer.h"
 #include "third_party/khronos/GLES2/gl2.h"
 #include "ui/gfx/geometry/size_conversions.h"
 #include "ui/gfx/skia_util.h"
 
 namespace content {
 
 ChildFrameCompositingHelper*
 ChildFrameCompositingHelper::CreateForBrowserPlugin(
     const base::WeakPtr<BrowserPlugin>& browser_plugin) {
   return new ChildFrameCompositingHelper(
-      browser_plugin, NULL, NULL, browser_plugin->render_frame_routing_id());
+      browser_plugin, nullptr, nullptr,
+      browser_plugin->render_frame_routing_id());
 }
 
 ChildFrameCompositingHelper*
 ChildFrameCompositingHelper::CreateForRenderFrameProxy(
     RenderFrameProxy* render_frame_proxy) {
   return new ChildFrameCompositingHelper(base::WeakPtr<BrowserPlugin>(),
                                          render_frame_proxy->web_frame(),
                                          render_frame_proxy,
                                          render_frame_proxy->routing_id());
 }
 
 ChildFrameCompositingHelper::ChildFrameCompositingHelper(
     const base::WeakPtr<BrowserPlugin>& browser_plugin,
     blink::WebFrame* frame,
     RenderFrameProxy* render_frame_proxy,
     int host_routing_id)
     : host_routing_id_(host_routing_id),
       last_route_id_(0),
       last_output_surface_id_(0),
       last_host_id_(0),
       ack_pending_(true),
       opaque_(true),
       browser_plugin_(browser_plugin),
       render_frame_proxy_(render_frame_proxy),
       frame_(frame) {}
 
 ChildFrameCompositingHelper::~ChildFrameCompositingHelper() {
   if (resource_collection_.get())
-    resource_collection_->SetClient(NULL);
+    resource_collection_->SetClient(nullptr);

[ncarter (slow), 2015/05/28 22:32:52]

We've given pointers to this object to the surface_layer_ (via the
satisfy/require callbacks). And the surface_layer_ is refcounted so it
presumably could outlive the CFCH.

What guarantees that the callbacks won't be invoked after the CFCH is deleted?

[kenrb, 2015/05/29 19:29:37]

I changed the arguments to weak pointers, because I couldn't find a reason why
that would never happen.

 }
 
 BrowserPluginManager* ChildFrameCompositingHelper::GetBrowserPluginManager() {
   if (!browser_plugin_)
-    return NULL;
+    return nullptr;
 
   return BrowserPluginManager::Get();
 }
 
 blink::WebPluginContainer* ChildFrameCompositingHelper::GetContainer() {
   if (!browser_plugin_)
-    return NULL;
+    return nullptr;
 
   return browser_plugin_->container();
 }
 
 int ChildFrameCompositingHelper::GetInstanceID() {
   if (!browser_plugin_)
     return 0;
 
   return browser_plugin_->browser_plugin_instance_id();
 }
@@ skipping 46 matching lines @@
   if (enable && !background_layer_.get()) {
     background_layer_ =
         cc::SolidColorLayer::Create(cc_blink::WebLayerImpl::LayerSettings());
     background_layer_->SetMasksToBounds(true);
     background_layer_->SetBackgroundColor(
         SkColorSetARGBInline(255, 255, 255, 255));
     web_layer_.reset(new cc_blink::WebLayerImpl(background_layer_));
   }
 
   if (GetContainer()) {
-    GetContainer()->setWebLayer(enable ? web_layer_.get() : NULL);
+    GetContainer()->setWebLayer(enable ? web_layer_.get() : nullptr);
   } else if (frame_) {
-    frame_->setRemoteWebLayer(enable ? web_layer_.get() : NULL);
+    frame_->setRemoteWebLayer(enable ? web_layer_.get() : nullptr);
   }
 }
 
 void ChildFrameCompositingHelper::CheckSizeAndAdjustLayerProperties(
     const gfx::Size& new_size,
     float device_scale_factor,
     cc::Layer* layer) {
   if (buffer_size_ != new_size) {
     buffer_size_ = new_size;
     // The container size is in DIP, so is the layer size.
     // Buffer size is in physical pixels, so we need to adjust
     // it by the device scale factor.
     gfx::Size device_scale_adjusted_size = gfx::ToFlooredSize(
         gfx::ScaleSize(buffer_size_, 1.0f / device_scale_factor));
     layer->SetBounds(device_scale_adjusted_size);
   }
 
   // Manually manage background layer for transparent webview.
   if (!opaque_)
     background_layer_->SetIsDrawable(false);
 }
 
 void ChildFrameCompositingHelper::OnContainerDestroy() {
   // If we have a pending ACK, then ACK now so we don't lose frames in the
   // future.
   DidCommitCompositorFrame();
 
   if (GetContainer())
-    GetContainer()->setWebLayer(NULL);
+    GetContainer()->setWebLayer(nullptr);
 
   if (resource_collection_.get())
-    resource_collection_->SetClient(NULL);
+    resource_collection_->SetClient(nullptr);
 
   ack_pending_ = false;
-  resource_collection_ = NULL;
-  frame_provider_ = NULL;
-  delegated_layer_ = NULL;
-  background_layer_ = NULL;
+  resource_collection_ = nullptr;
+  frame_provider_ = nullptr;
+  delegated_layer_ = nullptr;
+  background_layer_ = nullptr;
+  surface_layer_ = nullptr;
   web_layer_.reset();
 }
 
 void ChildFrameCompositingHelper::ChildFrameGone() {
   background_layer_->SetBackgroundColor(SkColorSetARGBInline(255, 0, 128, 0));
   background_layer_->RemoveAllChildren();
   background_layer_->SetIsDrawable(true);
   background_layer_->SetContentsOpaque(true);
 }
 
 void ChildFrameCompositingHelper::OnCompositorFrameSwapped(
     scoped_ptr<cc::CompositorFrame> frame,
     int route_id,
     uint32 output_surface_id,
     int host_id,
     base::SharedMemoryHandle handle) {
   cc::DelegatedFrameData* frame_data = frame->delegated_frame_data.get();
+
+  // Surface IDs and compositor frames should never be received
+  // interchangeably.
+  DCHECK(!surface_layer_.get());
+
   // Do nothing if we are getting destroyed or have no frame data.
   if (!frame_data || !background_layer_.get())
     return;
 
   DCHECK(!frame_data->render_pass_list.empty());
   cc::RenderPass* root_pass = frame_data->render_pass_list.back();
   gfx::Size frame_size = root_pass->output_rect.size();
 
   if (last_route_id_ != route_id ||
       last_output_surface_id_ != output_surface_id ||
       last_host_id_ != host_id) {
     // Resource ids are scoped by the output surface.
     // If the originating output surface doesn't match the last one, it
     // indicates the guest'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.
-    frame_provider_ = NULL;
+    frame_provider_ = nullptr;
 
     // Drop the cc::DelegatedFrameResourceCollection so that we will not return
     // any resources from the old output surface with the new output surface id.
     if (resource_collection_.get()) {
-      resource_collection_->SetClient(NULL);
+      resource_collection_->SetClient(nullptr);
 
       if (resource_collection_->LoseAllResources())
         SendReturnedDelegatedResources();
-      resource_collection_ = NULL;
+      resource_collection_ = nullptr;
     }
     last_output_surface_id_ = output_surface_id;
     last_route_id_ = route_id;
     last_host_id_ = host_id;
   }
   if (!resource_collection_.get()) {
     resource_collection_ = new cc::DelegatedFrameResourceCollection;
     resource_collection_->SetClient(this);
   }
   if (!frame_provider_.get() || frame_provider_->frame_size() != frame_size) {
@@ skipping 12 matching lines @@
   }
 
   CheckSizeAndAdjustLayerProperties(
       frame_data->render_pass_list.back()->output_rect.size(),
       frame->metadata.device_scale_factor,
       delegated_layer_.get());
 
   ack_pending_ = true;
 }
 
+// static
+void ChildFrameCompositingHelper::SatisfyCallback(
+    ChildFrameCompositingHelper* helper,
+    cc::SurfaceSequence sequence) {
+  if (helper->render_frame_proxy_) {
+    helper->render_frame_proxy_->Send(
+        new FrameHostMsg_SatisfySequence(helper->host_routing_id_, sequence));
+  }
+}
+
+// static
+void ChildFrameCompositingHelper::RequireCallback(
+    ChildFrameCompositingHelper* helper,
+    cc::SurfaceId id,
+    cc::SurfaceSequence sequence) {
+  if (helper->render_frame_proxy_) {
+    helper->render_frame_proxy_->Send(new FrameHostMsg_RequireSequence(
+        helper->host_routing_id_, id, sequence));
+  }
+}
+
+void ChildFrameCompositingHelper::OnSetSurface(
+    const cc::SurfaceId& surface_id,
+    const gfx::Size& frame_size,
+    float scale_factor,
+    const cc::SurfaceSequence& sequence) {
+  // Surface IDs and compositor frames should never be received
+  // interchangably.
+  DCHECK(!delegated_layer_.get());
+
+  // Do nothing if we are getting destroyed.
+  if (!background_layer_.get())
+    return;
+
+  if (!surface_layer_.get()) {
+    cc::SurfaceLayer::SatisfyCallback satisfy_callback = base::Bind(
+        &ChildFrameCompositingHelper::SatisfyCallback, base::Unretained(this));
+    cc::SurfaceLayer::RequireCallback require_callback = base::Bind(
+        &ChildFrameCompositingHelper::RequireCallback, base::Unretained(this));
+    surface_layer_ =
+        cc::SurfaceLayer::Create(cc_blink::WebLayerImpl::LayerSettings(),
+                                 satisfy_callback, require_callback);
+  }
+  surface_layer_->SetSurfaceId(surface_id, scale_factor, frame_size);
+  UpdateVisibility(true);
+  SetContentsOpaque(opaque_);
+  background_layer_->AddChild(surface_layer_);
+
+  // The RWHV creates a destruction dependency on the surface that needs to be
+  // satisfied.
+  render_frame_proxy_->Send(
+      new FrameHostMsg_SatisfySequence(host_routing_id_, sequence));
+
+  CheckSizeAndAdjustLayerProperties(frame_size, scale_factor,
+                                    surface_layer_.get());
+}
+
 void ChildFrameCompositingHelper::UpdateVisibility(bool visible) {
   if (delegated_layer_.get())
     delegated_layer_->SetIsDrawable(visible);
+  if (surface_layer_.get())
+    surface_layer_->SetIsDrawable(visible);
 }
 
 void ChildFrameCompositingHelper::UnusedResourcesAreAvailable() {
   if (ack_pending_)
     return;
 
   SendReturnedDelegatedResources();
 }
 
 void ChildFrameCompositingHelper::SendReturnedDelegatedResources() {
   FrameHostMsg_ReclaimCompositorResources_Params params;
   if (resource_collection_.get())
     resource_collection_->TakeUnusedResourcesForChildCompositor(
         &params.ack.resources);
   DCHECK(!params.ack.resources.empty());
 
   params.route_id = last_route_id_;
   params.output_surface_id = last_output_surface_id_;
   params.renderer_host_id = last_host_id_;
   SendReclaimCompositorResourcesToBrowser(params);
 }
 
 void ChildFrameCompositingHelper::SetContentsOpaque(bool opaque) {
   opaque_ = opaque;
   if (delegated_layer_.get())
     delegated_layer_->SetContentsOpaque(opaque_);
+  if (surface_layer_.get())
+    surface_layer_->SetContentsOpaque(opaque_);
 }
 
 }  // namespace content