DialogSurfaceManager implementation.

media/base/android/dialog_surface.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 MEDIA_BASE_ANDROID_DIALOG_SURFACE_H_
+#define MEDIA_BASE_ANDROID_DIALOG_SURFACE_H_
+
+#include <jni.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include <set>
+#include <string>
+
+#include "base/android/scoped_java_ref.h"
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/task_runner.h"
+#include "base/threading/thread_checker.h"
+#include "base/time/time.h"
+#include "media/base/media_export.h"
+#include "ui/gfx/geometry/rect.h"
+#include "ui/gl/android/scoped_java_surface.h"
+
+namespace media {
+
+class DialogSurfaceCallback;
+class DialogSurfaceManager;
+
+// This class implements the C++ wrapper around a java DialogSurface.
+// All callbacks happen on the thread that it's constructed on.
+class MEDIA_EXPORT DialogSurface {
+ public:
+  // These must match DialogSurface.java
+  enum CallbackOp { SURFACE_CREATED = 0, SURFACE_DESTROYED = 1 };
+
+  // Callback type for finding out about the status of the surface.  While we
+  // don't use this directly, it lets us keep DialogSurfaceCallback as an
+  // implementation detail.
+  using Callback = base::Callback<void(CallbackOp)>;
+
+  // Configuration for the surface.

[DaleCurtis, 2016/08/04 00:20:36]

Is it worth keeping this as a struct? I.e., how soon do you expect there to be
more than one element? 

[liberato (no reviews please), 2016/08/04 01:06:20]

is_secure will be showing up before too long, i think.  format will be needed if
we ever use these outside of mediacodec.

+  struct Config {
+    gfx::Rect rect;
+    // This may also include pixel format, is_secure, etc.
+  };
+
+  // Schedule a relayout and/or reposition of the surface.
+  // void ScheduleLayout(const Config& config);
+
+  // Return the java surface, if any.  One should not assume that this is
+  // available immediately.  The callback will be called with SURFACE_CREATED
+  // when it is available.  Of course, it may become unavailable again
+  // asynchronously, so one must always check.
+  // gl::ScopedJavaSurface GetSurface();
+};
+
+}  // namespace media
+
+#endif  // MEDIA_BASE_ANDROID_DIALOG_SURFACE_H_