Add initial Blink-side support for the Screen Orientation API

public/web/WebScreenOrientation.h

Index: public/web/WebScreenOrientation.h
diff --git a/public/web/WebScreenOrientation.h b/public/web/WebScreenOrientation.h
new file mode 100644
index 0000000000000000000000000000000000000000..ed9684c8fc15c6139b7e8992ccfd9565ee836c5a
--- /dev/null
+++ b/public/web/WebScreenOrientation.h
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+// Copyright 2014 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 WebScreenOrientation_h
+#define WebScreenOrientation_h
+
+namespace blink {
+
+enum WebScreenOrientation {
+    WebScreenOrientationPortraitPrimary = 1,
+    WebScreenOrientationLandscapePrimary = 1 << 1,
+    WebScreenOrientationPortraitSecondary = 1 << 2,
+    WebScreenOrientationLandscapeSecondary = 1 << 3,
+};
+
+typedef unsigned char WebScreenOrientations;
+
+} // namespace blink
+
+#endif // WebScreenOrientation_h