Allow going fullscreen during a screen orientation change handler.

third_party/WebKit/Source/platform/ScopedOrientationChangeIndicator.h

Index: third_party/WebKit/Source/platform/ScopedOrientationChangeIndicator.h
diff --git a/third_party/WebKit/Source/platform/ScopedOrientationChangeIndicator.h b/third_party/WebKit/Source/platform/ScopedOrientationChangeIndicator.h
new file mode 100644
index 0000000000000000000000000000000000000000..a51db2d6d6570c71f749b8e50b02bd4cddf7efc2
--- /dev/null
+++ b/third_party/WebKit/Source/platform/ScopedOrientationChangeIndicator.h
@@ -0,0 +1,36 @@
+// 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 ScopedOrientationChangeIndicator_h
+#define ScopedOrientationChangeIndicator_h
+
+#include "platform/PlatformExport.h"
+#include "wtf/Allocator.h"
+#include "wtf/Noncopyable.h"
+
+namespace blink {
+
+class PLATFORM_EXPORT ScopedOrientationChangeIndicator final {
+    STACK_ALLOCATED();
+    WTF_MAKE_NONCOPYABLE(ScopedOrientationChangeIndicator);
+public:
+    static bool processingOrientationChange();
+
+    explicit ScopedOrientationChangeIndicator();
+    ~ScopedOrientationChangeIndicator();
+
+private:
+    enum class State {
+        Processing,
+        NotProcessing,
+    };
+
+    static State s_state;
+
+    State m_previousState = State::NotProcessing;
+};
+
+} // namespace blink
+
+#endif