Add methods for creating V8 extras-based ReadableStreams from C++

third_party/WebKit/Source/bindings/core/v8/ToV8.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 ToV8_h
 #define ToV8_h
 
 // toV8() provides C++ -> V8 conversion. Note that toV8() can return an empty
 // handle. Call sites must check IsEmpty() before using return value.
 
@@ skipping 168 matching lines @@
     DISALLOW_NEW();
 }; // Used only for having toV8 return v8::Undefined.
 
 inline v8::Local<v8::Value> toV8(const ToV8UndefinedGenerator&  value, v8::Local<v8::Object> creationContext, v8::Isolate* isolate)
 {
     return v8::Undefined(isolate);
 }
 
 // ScriptValue
 
 inline v8::Local<v8::Value> toV8(const ScriptValue& value, v8::Local<v8::Object> creationContext, v8::Isolate*)

[haraken, 2016/02/09 01:19:29]

Alternately, can we move this implementation to ToV8.cpp and remove '#include
ScriptValue.h' from ToV8.h?

 {
     return value.v8Value();
 }
 
 // Dictionary
 
 inline v8::Local<v8::Value> toV8(const Dictionary& value, v8::Local<v8::Object> creationContext, v8::Isolate*)
 {
     RELEASE_ASSERT_NOT_REACHED();
     return v8::Local<v8::Value>();
@@ skipping 55 matching lines @@
 // Only declare toV8(void*,...) for checking function overload mismatch.
 // This toV8(void*,...) should be never used. So we will find mismatch
 // because of "unresolved external symbol".
 // Without toV8(void*, ...), call to toV8 with T* will match with
 // toV8(bool, ...) if T is not a subclass of ScriptWrappable or if T is
 // declared but not defined (so it's not clear that T is a subclass of
 // ScriptWrappable).
 // This hack helps detect such unwanted implicit conversions from T* to bool.
 v8::Local<v8::Value> toV8(void* value, v8::Local<v8::Object> creationContext, v8::Isolate*) = delete;
 
+// Cannot define in ScriptValue because of the circular dependency between toV8 and ScriptValue
+template<typename T>
+inline ScriptValue ScriptValue::from(ScriptState* scriptState, T&& value)
+{
+    return ScriptValue(scriptState, toV8(std::forward<T>(value), scriptState));
+}
+
 } // namespace blink
 
 #endif // ToV8_h