Use per-frame TaskRunner instead of thread's default in DataConsumerHandle

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

Index: third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.cpp
diff --git a/third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.cpp b/third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.cpp
index bbfc917052e078b816cc3c646fa04c7ed86b20e1..f9fd9b7a513217864b0f94b96c4a539e3814cd27 100644
--- a/third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.cpp
+++ b/third_party/WebKit/Source/modules/fetch/ReadableStreamDataConsumerHandle.cpp
@@ -115,10 +115,10 @@ public:
 
     class ReaderImpl final : public FetchDataConsumerHandle::Reader {
     public:
-        ReaderImpl(PassRefPtr<ReadingContext> context, Client* client)
+        ReaderImpl(PassRefPtr<ReadingContext> context, Client* client, std::unique_ptr<WebTaskRunner> readerTaskRunner)
             : m_readingContext(context)
         {
-            m_readingContext->attachReader(client);
+            m_readingContext->attachReader(client, std::move(readerTaskRunner));
         }
         ~ReaderImpl() override
         {
@@ -144,9 +144,10 @@ public:
         return adoptRef(new ReadingContext(scriptState, streamReader));
     }
 
-    void attachReader(WebDataConsumerHandle::Client* client)
+    void attachReader(WebDataConsumerHandle::Client* client, std::unique_ptr<WebTaskRunner> readerTaskRunner)
     {
         m_client = client;
+        m_readerTaskRunner = std::move(readerTaskRunner);
         notifyLater();
     }
 
@@ -242,7 +243,7 @@ public:
     void notifyLater()
     {
         ASSERT(m_client);
-        Platform::current()->currentThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, WTF::bind(&ReadingContext::notify, PassRefPtr<ReadingContext>(this)));
+        m_readerTaskRunner->postTask(BLINK_FROM_HERE, WTF::bind(&ReadingContext::notify, PassRefPtr<ReadingContext>(this)));

[haraken, 2016/07/27 11:05:25]

For example, you can avoid adding m_readerTaskRunner by using
TaskRunnerHelper::getUnthrottledTaskRunner(m_scriptState.get()).

[tzik, 2016/07/27 14:59:41]

Done.
Frame/Document/ScriptState seem not available in other use cases.

     }
 
 private:
@@ -280,6 +281,7 @@ private:
     ScopedPersistent<v8::Value> m_reader;
     RefPtr<ScriptState> m_scriptState;
     WebDataConsumerHandle::Client* m_client;
+    std::unique_ptr<WebTaskRunner> m_readerTaskRunner;
     Persistent<DOMUint8Array> m_pendingBuffer;
     size_t m_pendingOffset;
     bool m_isReading;
@@ -293,9 +295,9 @@ ReadableStreamDataConsumerHandle::ReadableStreamDataConsumerHandle(ScriptState*
 }
 ReadableStreamDataConsumerHandle::~ReadableStreamDataConsumerHandle() = default;
 
-std::unique_ptr<FetchDataConsumerHandle::Reader> ReadableStreamDataConsumerHandle::obtainFetchDataReader(Client* client)
+std::unique_ptr<FetchDataConsumerHandle::Reader> ReadableStreamDataConsumerHandle::obtainFetchDataReader(Client* client, std::unique_ptr<WebTaskRunner> readerTaskRunner)
 {
-    return WTF::wrapUnique(new ReadingContext::ReaderImpl(m_readingContext, client));
+    return WTF::wrapUnique(new ReadingContext::ReaderImpl(m_readingContext, client, std::move(readerTaskRunner)));
 }
 
 } // namespace blink