Add a full Blimp integration test.

blimp/engine/browser_tests/blimp_contents_view_readback_helper.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 BLIMP_ENGINE_BROWSER_TESTS_BLIMP_CONTENTS_VIEW_READBACK_HELPER_H_
+#define BLIMP_ENGINE_BROWSER_TESTS_BLIMP_CONTENTS_VIEW_READBACK_HELPER_H_
+
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "base/synchronization/waitable_event.h"
+#include "blimp/client/public/contents/blimp_contents_view.h"
+
+namespace blimp {
+
+// A helper class to make grabbing a bitmap from a BlimpContentsView easier.
+// This can be used in conjunction with a WaitableContentPump to pause test
+// execution while waiting for the readback to finish.  An example use would be:
+//
+// WaitableContentPump pump;
+// BlimpContentsViewReadbackHelper helper;
+// blimp_contents->GetView()->CopyCompositingSurface(
+//    helper.GetCallback(), true);
+// pump.WaitFor(helper.event());
+// helper.bitmap();
+
+class BlimpContentsViewReadbackHelper {
+ public:
+  BlimpContentsViewReadbackHelper();
+  virtual ~BlimpContentsViewReadbackHelper();
+
+  client::BlimpContentsView::ReadbackRequestCallback GetCallback();
+  SkBitmap* GetBitmap() const;
+
+  base::WaitableEvent* event() { return &event_; }
+
+ private:
+  void OnReadbackComplete(std::unique_ptr<SkBitmap> bitmap);
+
+  base::WaitableEvent event_;
+  std::unique_ptr<SkBitmap> bitmap_;
+
+  base::WeakPtrFactory<BlimpContentsViewReadbackHelper> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(BlimpContentsViewReadbackHelper);
+};
+
+}  // namespace blimp
+
+#endif  // BLIMP_ENGINE_BROWSER_TESTS_BLIMP_CONTENTS_VIEW_READBACK_HELPER_H_