Reland: Script streaming: Add an option to make the main thread block (wait for parsing)

Source/bindings/core/v8/ScriptStreamingMode.h

+// 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 ScriptStreamingMode_h
+#define ScriptStreamingMode_h
+
+// ScriptStreamingModes are used for evaluating different heuristics for when we
+// should start streaming.
+
+namespace blink {
+
+enum ScriptStreamingMode {
+    // Stream all scripts
+    ScriptStreamingModeAll,
+    // Stream only async and deferred scripts
+    ScriptStreamingModeOnlyAsyncAndDefer,
+    // Stream all scripts, block the main thread after loading when streaming
+    // parser blocking scripts.
+    ScriptStreamingModeAllPlusBlockParsingBlocking
+};
+
+} // namespace blink
+
+#endif // ScriptStreamingMode_h