[Fetch API] Fix a memory leak with a Response constructed with a ReadableStream

third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.h

Index: third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.h
diff --git a/third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.h b/third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.h
index 9c634f73d990d6da1e947994a59f1d2c7e7f6080..1da11b4bfa2573adee1a22cd1cf6e65eb2e2864e 100644
--- a/third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.h
+++ b/third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.h
@@ -20,23 +20,24 @@ class ScriptState;
 // implemented with V8 Extras.
 // The stream will be immediately locked by the handle and will never be
 // released.
+//
+// The ReadableStreamReader handle held in a ReadableStreamDataConsumerHandle
+// is weak. A user must guarantee that the ReadableStreamReader object is kept
+// alive appropriately.
 // TODO(yhirano): CURRENTLY THIS HANDLE SUPPORTS READING ONLY FROM THE THREAD ON
 // WHICH IT IS CREATED. FIX THIS.
-// TODO(yhirano): This implementation may cause leaks because the handle and
-// the reader own a strong reference to the associated ReadableStreamReader.
-// Fix it.
 class MODULES_EXPORT ReadableStreamDataConsumerHandle final : public FetchDataConsumerHandle {
     WTF_MAKE_NONCOPYABLE(ReadableStreamDataConsumerHandle);
 public:
-    static PassOwnPtr<ReadableStreamDataConsumerHandle> create(ScriptState* scriptState, v8::Local<v8::Value> stream)
+    static PassOwnPtr<ReadableStreamDataConsumerHandle> create(ScriptState* scriptState, v8::Local<v8::Object> streamReader)
     {
-        return adoptPtr(new ReadableStreamDataConsumerHandle(scriptState, stream));
+        return adoptPtr(new ReadableStreamDataConsumerHandle(scriptState, streamReader));
     }
     ~ReadableStreamDataConsumerHandle() override;
 
 private:
     class ReadingContext;
-    ReadableStreamDataConsumerHandle(ScriptState*, v8::Local<v8::Value> stream);
+    ReadableStreamDataConsumerHandle(ScriptState*, v8::Local<v8::Object> streamReader);
     Reader* obtainReaderInternal(Client*) override;
     const char* debugName() const override { return "ReadableStreamDataConsumerHandle"; }