Add AndroidVideoSurfaceChooser to manage overlays.

media/base/android/test_destruction_observable.h

Index: media/base/android/test_destruction_observable.h
diff --git a/media/base/android/test_destruction_observable.h b/media/base/android/test_destruction_observable.h
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index 0000000000000000000000000000000000000000..b1676fbf55ad2d9dd8c661c7e43a84e722c5238d
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+++ b/media/base/android/test_destruction_observable.h
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+// 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.
+
+#ifndef MEDIA_BASE_ANDROID_TEST_DESTRUCTION_OBSERVABLE_H_
+#define MEDIA_BASE_ANDROID_TEST_DESTRUCTION_OBSERVABLE_H_
+
+#include "base/callback.h"
+#include "base/memory/weak_ptr.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+namespace media {
+
+// Utility class to help tests set expectations about the lifetime of mocks that
+// they don't own.  The mocks in question must derive from
+// DestructionObservable.  The test can call CreateDestructionObserver() to
+// create the observer on which it may set expectations.  By default, is is okay
+// but not required to destroy the observable.
+class DestructionObservable {
+ private:
+  class DestructionObserverInterface {
+   public:
+    DestructionObserverInterface() = default;
+    virtual ~DestructionObserverInterface() {}
+
+    virtual void OnDestroyed() = 0;
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(DestructionObserverInterface);
+  };
+
+ public:
+  // Mock that calls OnDestroyed when the observable is destroyed.  This
+  // will replace the destruction callback on the mock.
+  class DestructionObserver : testing::NiceMock<DestructionObserverInterface> {
+   protected:
+    DestructionObserver();
+
+   public:
+    ~DestructionObserver();
+
+    // Make destruction optional.  This will not fail even if destruction has
+    // already occured.  Useful if you want to verify that ExpectDestruction()
+    // has succeeded by the time this is called.
+    void DestructionIsOptional();
+
+    // Indicate that the object must be destroyed before the observer is, or
+    // before the expectation is changed.  Normally, the only reasonable next
+    // expecation is DestructionIsOptional, to verify that the codec has been
+    // destroyed by a certain point in the test.
+    //
+    // Note that if the object has already been destroyed, then this call will
+    // fail the test; either some previous expectation of ours should have
+    // failed (e.g., DoNotAllowDestruction, but the object was destroyed), in
+    // which case us failing is fine.  Or, if no previous expectation failed,
+    // then it's likely that the test didn't set expectations properly.
+    void ExpectDestruction();
+
+    // Indicate that the observable may not be destroyed before the observer
+    // is destroyed, or the expection is changed.  This will fail immediately
+    // if the observable has already been destroyed.
+    void DoNotAllowDestruction();
+
+   private:
+    friend class DestructionObservable;
+
+    // Return a callback gthat will notify us about destruction.
+    base::Closure GetCallback();
+
+    // Called by the callback when the observable is destroyed.
+    void OnDestroyed();
+
+    // Called by OnDestroyed, so that we can set expectations on it.
+    MOCK_METHOD0(MockOnDestroyed, void());
+
+    // Has the observable been destroyed already?
+    bool destroyed_ = false;
+
+    base::WeakPtrFactory<DestructionObserver> weak_factory_;
+
+    DISALLOW_COPY_AND_ASSIGN(DestructionObserver);
+  };
+
+  DestructionObservable();
+  virtual ~DestructionObservable();
+
+  // Create a DestructionObserver for us.  There can be only one.
+  std::unique_ptr<DestructionObserver> CreateDestructionObserver();
+
+ private:
+  // Callback that we'll call when we're destroyed.
+  base::Closure destruction_cb_;
+
+  DISALLOW_COPY_AND_ASSIGN(DestructionObservable);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_BASE_ANDROID_TEST_DESTRUCTION_OBSERVABLE_H_