Add a Display and ContextProvider concept to mojom, use to recreate

services/surfaces/display_impl.cc

+// Copyright 2015 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 "services/surfaces/display_impl.h"
+
+#include "cc/output/compositor_frame.h"
+#include "cc/surfaces/display.h"
+#include "mojo/cc/context_provider_mojo.h"
+#include "mojo/cc/direct_output_surface.h"
+#include "mojo/converters/geometry/geometry_type_converters.h"
+#include "mojo/converters/surfaces/surfaces_type_converters.h"
+#include "services/surfaces/surfaces_scheduler.h"
+
+namespace surfaces {
+namespace {
+void CallCallback(const mojo::Closure& callback, cc::SurfaceDrawStatus status) {
+  callback.Run();
+}
+}
+
+DisplayImpl::DisplayImpl(cc::SurfaceManager* manager,
+                         cc::SurfaceId cc_id,
+                         SurfacesScheduler* scheduler,
+                         mojo::ContextProviderPtr context_provider,
+                         mojo::ResourceReturnerPtr returner,
+                         mojo::InterfaceRequest<mojo::Display> display_request)
+    : manager_(manager),
+      factory_(manager, this),
+      cc_id_(cc_id),
+      scheduler_(scheduler),
+      context_provider_(context_provider.Pass()),
+      returner_(returner.Pass()),
+      viewport_param_binding_(this),
+      display_binding_(this, display_request.Pass()) {
+  mojo::ViewportParameterListenerPtr viewport_parameter_listener;
+  viewport_param_binding_.Bind(GetProxy(&viewport_parameter_listener));
+  context_provider_->Create(
+      viewport_parameter_listener.Pass(),
+      base::Bind(&DisplayImpl::OnContextCreated, base::Unretained(this)));
+}
+
+void DisplayImpl::OnContextCreated(mojo::CommandBufferPtr gles2_client) {
+  if (!display_) {

[qsr, 2015/02/23 12:32:53]

When do we expect display to not be null? If I understand correctly, we get
there only from the constructor of this object, so this should never happen.
Should this be a DCHECK?

[jamesr, 2015/03/04 00:19:51]

You're right, this could be a DCHECK now.  When the TODO on line 48 is resolved
then we'll get to this path after a lost context and will need to recreate a
display but that's for a later time.

Changed to a DCHECK

+    cc::RendererSettings settings;
+    display_.reset(new cc::Display(this, manager_, nullptr, nullptr, settings));
+    scheduler_->AddDisplay(display_.get());
+    // TODO: Listen to lost context events and request a new one from
+    // |context_provider_|.
+    display_->Initialize(make_scoped_ptr(new mojo::DirectOutputSurface(
+        new mojo::ContextProviderMojo(gles2_client.PassMessagePipe()))));
+  }
+  factory_.Create(cc_id_);

[qsr, 2015/02/23 12:32:53]

I'm probably missing something, but where is this surface destroyed? We are not
doing it here, and I do not see any destory call in display either.

[jamesr, 2015/03/04 00:19:51]

It's destroyed implicitly by destroying the factory, which destroys all surfaces
constructed via the factory, but having it be more explicit is probably better. 
I'll add a Destroy call in ~DisplayImpl

+  display_->SetSurfaceId(cc_id_, 1.f);
+  if (pending_frame_)
+    Draw();
+}
+
+DisplayImpl::~DisplayImpl() {
+  if (display_)
+    scheduler_->RemoveDisplay(display_.get());
+}
+
+void DisplayImpl::SubmitFrame(mojo::FramePtr frame,
+                              const SubmitFrameCallback& callback) {
+  DCHECK(pending_callback_.is_null());
+  pending_frame_ = frame.Pass();
+  pending_callback_ = callback;
+  if (display_)
+    Draw();
+}
+
+void DisplayImpl::Draw() {
+  gfx::Size frame_size =
+      pending_frame_->passes[0]->output_rect.To<gfx::Rect>().size();
+  display_->Resize(frame_size);
+  factory_.SubmitFrame(cc_id_,
+                       pending_frame_.To<scoped_ptr<cc::CompositorFrame>>(),
+                       base::Bind(&CallCallback, pending_callback_));
+  scheduler_->SetNeedsDraw();
+  pending_callback_.reset();
+}
+
+void DisplayImpl::DisplayDamaged() {
+}
+
+void DisplayImpl::DidSwapBuffers() {
+}
+
+void DisplayImpl::DidSwapBuffersComplete() {
+}
+
+void DisplayImpl::CommitVSyncParameters(base::TimeTicks timebase,
+                                        base::TimeDelta interval) {
+}
+
+void DisplayImpl::OutputSurfaceLost() {
+}
+
+void DisplayImpl::SetMemoryPolicy(const cc::ManagedMemoryPolicy& policy) {
+}
+
+void DisplayImpl::OnVSyncParametersUpdated(int64_t timebase, int64_t interval) {
+  scheduler_->OnVSyncParametersUpdated(
+      base::TimeTicks::FromInternalValue(timebase),
+      base::TimeDelta::FromInternalValue(interval));
+}
+
+void DisplayImpl::ReturnResources(const cc::ReturnedResourceArray& resources) {
+  if (resources.empty())
+    return;
+  DCHECK(returner_);
+
+  mojo::Array<mojo::ReturnedResourcePtr> ret(resources.size());
+  for (size_t i = 0; i < resources.size(); ++i) {
+    ret[i] = mojo::ReturnedResource::From(resources[i]);
+  }
+  returner_->ReturnResources(ret.Pass());
+}
+
+}  // namespace surfaces