Add ScopedSurfaceRequestManager

content/browser/android/scoped_surface_request_manager.h

+// 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.
+
+#ifndef CONTENT_BROWSER_ANDROID_SCOPED_SURFACE_REQUEST_MANAGER_H_
+#define CONTENT_BROWSER_ANDROID_SCOPED_SURFACE_REQUEST_MANAGER_H_
+
+#include <unordered_map>
+
+#include "base/macros.h"
+#include "base/memory/singleton.h"
+#include "content/common/content_export.h"
+#include "gpu/ipc/common/android/scoped_surface_request_conduit.h"
+#include "ui/gl/android/scoped_java_surface.h"
+
+namespace content {
+
+class CONTENT_EXPORT ScopedSurfaceRequestManager
+    : public gpu::ScopedSurfaceRequestConduit {
+ public:
+  static ScopedSurfaceRequestManager* GetInstance();
+
+  using ScopedSurfaceRequestCB = base::Callback<void(gl::ScopedJavaSurface)>;
+
+  void RegisterScopedSurfaceRequest(uint64_t request_id,

[watk, 2016/08/29 19:42:26]

Without comments it kinda sounds like this gets you a surface without you doing
anything. But the caller is responsible for organizing for the surface to be
delivered.

+                                    ScopedSurfaceRequestCB request_cb);
+
+  // Unregisters and returns a request previously registered by this class'
+  // Register method.
+  // Returns a default ScopedSurfaceRequestCB if there was no request associated
+  // with |request_id|.
+  ScopedSurfaceRequestCB GetAndUnregisterScopedSurfaceRequest(
+      uint64_t request_id);
+
+  // gpu::ScopedSurfaceRequestConduit implementation
+  //
+  // Runs the request identified by |request_id| if one exists.
+  // Runs the callback on the current thread.

[watk, 2016/08/29 19:42:26]

Not only on the current thread but synchronously. (Unless you implemented logic
to post to self).

+  // Used when in single process mode (see ChildProcessServices otherwise).
+  void FulfillScopedSurfaceRequest(
+      uint64_t request_id,
+      gl::SurfaceTexture* surface_texture) override;
+
+  void clear_callbacks_for_testing() { request_callbacks_.clear(); }
+
+  int callback_count_for_testing() { return request_callbacks_.size(); }
+
+ private:
+  friend struct base::DefaultSingletonTraits<ScopedSurfaceRequestManager>;
+
+  // Unregisters and returns the request identified by |request_id|.
+  // Does not acquire |lock_|.
+  ScopedSurfaceRequestCB GetAndUnregisterInternal(uint64_t request_id);
+
+  // Map used to hold references to the registered callbacks.
+  std::unordered_map<uint64_t, ScopedSurfaceRequestCB> request_callbacks_;
+
+  // Used to protect |request_callbacks_|.
+  base::Lock lock_;
+
+  ScopedSurfaceRequestManager();
+  ~ScopedSurfaceRequestManager() override;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedSurfaceRequestManager);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_ANDROID_SCOPED_SURFACE_REQUEST_MANAGER_H_