Use GVR async reprojection video surface for fullscreen in VR shell

content/browser/media/android/video_surface_manager_impl.cc

+// Copyright 2017 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/media/android/video_surface_manager_impl.h"
+
+#include "content/browser/android/content_video_view.h"
+#include "content/browser/web_contents/web_contents_impl.h"
+#include "content/public/browser/web_contents_delegate.h"
+
+namespace content {
+
+static base::LazyInstance<VideoSurfaceManagerImpl>::Leaky g_surface_manager =
+    LAZY_INSTANCE_INITIALIZER;
+
+// static
+VideoSurfaceManager* VideoSurfaceManager::GetInstance() {
+  return VideoSurfaceManagerImpl::GetInstance();
+}
+
+// static
+VideoSurfaceManagerImpl* VideoSurfaceManagerImpl::GetInstance() {
+  return g_surface_manager.Pointer();
+}
+
+VideoSurfaceManagerImpl::VideoSurfaceManagerImpl() {}
+
+VideoSurfaceManagerImpl::~VideoSurfaceManagerImpl() {}
+
+void VideoSurfaceManagerImpl::SetOverrideVideoSurfaceProvider(
+    VideoSurfaceProvider* provider) {
+  // Make sure current provider isn't already set (it shouldn't be because
+  // entering vr (which would set an override) requires pausing chrome (which
+  // should exit fullscreen and remove any existing cvv instances).
+  // TODO(amp): Handle switching surface providers when/if VR changes to not
+  // exit full screen on transition.
+
+  // I have no idea if this is an appropriate way to handle pointers params.
+  current_provider_.reset(provider);
+}
+
+void VideoSurfaceManagerImpl::RemoveOverrideVideoSurfaceProvider(
+    VideoSurfaceProvider* provider) {
+  // Make sure the current provider is actually the passed in provider
+  current_provider_.reset();
+}
+
+VideoSurfaceProvider* VideoSurfaceManagerImpl::GetVideoSurfaceProvider(
+    WebContents* web_contents) {
+
+  if (!current_provider_) {
+    // If we don't own the fullscreen view, but one exists, it means another
+    // WebContents has it. Ignore the request and return a null surface
+    // provider.
+    if (ContentVideoView::GetInstance()) {
+      return nullptr;
+    }
+
+    ContentViewCore* cvc = ContentViewCore::FromWebContents(web_contents);
+    current_provider_.reset(new ContentVideoView(
+        cvc, web_contents->GetDelegate()->GetContentVideoViewEmbedder()));
+  }
+  // Also for returning pointers, is this ok, or should it be something else?
+  return current_provider_.get();
+}
+
+}  // namespace content