Introduce DataConsumerHandleTee

Source/modules/fetch/DataConsumerTee.h

Index: Source/modules/fetch/DataConsumerTee.h
diff --git a/Source/modules/fetch/DataConsumerTee.h b/Source/modules/fetch/DataConsumerTee.h
new file mode 100644
index 0000000000000000000000000000000000000000..4784c4f6006161f4da3d04473a63589fa1713f90
--- /dev/null
+++ b/Source/modules/fetch/DataConsumerTee.h
@@ -0,0 +1,25 @@
+// Copyright 2015 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 DataConsumerTee_h
+#define DataConsumerTee_h
+
+#include "public/platform/WebDataConsumerHandle.h"
+
+#include "wtf/OwnPtr.h"
+#include "wtf/PassOwnPtr.h"
+
+namespace blink {
+
+class ExecutionContext;
+
+class DataConsumerTee {
+public:
+    // Create two handles from one. |in| must be a valid unlocked handle.
+    static void create(ExecutionContext*, PassOwnPtr<WebDataConsumerHandle> in, OwnPtr<WebDataConsumerHandle>* out1, OwnPtr<WebDataConsumerHandle>* out2);

[hiroshige, 2015/06/19 06:40:35]

nit: Should we name the argument as |src|, |dest1/2| etc. to make the
declaration consistent with the definition and the comments in .cpp?

[yhirano, 2015/06/19 07:27:52]

Done.

+};
+
+} // namespace blink
+
+#endif // DataConsumerTee_h