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

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

Index: third_party/WebKit/Source/modules/fetch/DataConsumerHandleUtil.cpp
diff --git a/third_party/WebKit/Source/modules/fetch/DataConsumerHandleUtil.cpp b/third_party/WebKit/Source/modules/fetch/DataConsumerHandleUtil.cpp
index ac28f5d7bcd0ccd2bb26c71f1753a905de73a401..246f32b6888ae761c6648a4f1fd0567d8f85b0cf 100644
--- a/third_party/WebKit/Source/modules/fetch/DataConsumerHandleUtil.cpp
+++ b/third_party/WebKit/Source/modules/fetch/DataConsumerHandleUtil.cpp
@@ -34,14 +34,16 @@ private:
             return UnexpectedError;
         }
     };
-    std::unique_ptr<Reader> obtainReader(Client*) override { return WTF::wrapUnique(new ReaderImpl); }
+    std::unique_ptr<Reader> obtainReader(Client*, std::unique_ptr<WebTaskRunner>) override { return WTF::wrapUnique(new ReaderImpl); }
 
     const char* debugName() const override { return "WaitingHandle"; }
 };
 
 class RepeatingReader final : public WebDataConsumerHandle::Reader {
 public:
-    explicit RepeatingReader(Result result, WebDataConsumerHandle::Client* client) : m_result(result), m_notifier(client) { }
+    explicit RepeatingReader(Result result, WebDataConsumerHandle::Client* client, std::unique_ptr<WebTaskRunner> readerTaskRunner)
+        : m_result(result)
+        , m_notifier(client, readerTaskRunner.get()) { }
 
 private:
     Result beginRead(const void** buffer, WebDataConsumerHandle::Flags, size_t *available) override
@@ -61,13 +63,19 @@ private:
 
 class DoneHandle final : public WebDataConsumerHandle {
 private:
-    std::unique_ptr<Reader> obtainReader(Client* client) override { return WTF::wrapUnique(new RepeatingReader(Done, client)); }
+    std::unique_ptr<Reader> obtainReader(Client* client, std::unique_ptr<WebTaskRunner> readerTaskRunner) override
+    {
+        return WTF::wrapUnique(new RepeatingReader(Done, client, std::move(readerTaskRunner)));
+    }
     const char* debugName() const override { return "DoneHandle"; }
 };
 
 class UnexpectedErrorHandle final : public WebDataConsumerHandle {
 private:
-    std::unique_ptr<Reader> obtainReader(Client* client) override { return WTF::wrapUnique(new RepeatingReader(UnexpectedError, client)); }
+    std::unique_ptr<Reader> obtainReader(Client* client, std::unique_ptr<WebTaskRunner> readerTaskRunner) override
+    {
+        return WTF::wrapUnique(new RepeatingReader(UnexpectedError, client, std::move(readerTaskRunner)));
+    }
     const char* debugName() const override { return "UnexpectedErrorHandle"; }
 };
 
@@ -95,9 +103,9 @@ private:
         std::unique_ptr<WebDataConsumerHandle::Reader> m_reader;
     };
 
-    std::unique_ptr<Reader> obtainFetchDataReader(Client* client) override
+    std::unique_ptr<Reader> obtainFetchDataReader(Client* client, std::unique_ptr<WebTaskRunner> readerTaskRunner) override
     {
-        return WTF::wrapUnique(new ReaderImpl(m_handle->obtainReader(client)));
+        return WTF::wrapUnique(new ReaderImpl(m_handle->obtainReader(client, std::move(readerTaskRunner))));
     }
 
     const char* debugName() const override { return m_handle->debugName(); }
@@ -127,14 +135,15 @@ std::unique_ptr<FetchDataConsumerHandle> createFetchDataConsumerHandleFromWebHan
     return wrapUnique(new WebToFetchDataConsumerHandleAdapter(std::move(handle)));
 }
 
-NotifyOnReaderCreationHelper::NotifyOnReaderCreationHelper(WebDataConsumerHandle::Client* client)
+NotifyOnReaderCreationHelper::NotifyOnReaderCreationHelper(WebDataConsumerHandle::Client* client, WebTaskRunner* taskRunner)
     : m_factory(this)
 {
+    DCHECK(taskRunner->runsTasksOnCurrentThread());
     if (!client)
         return;
     // Note we don't need thread safety here because this object is
     // bound to the current thread.
-    Platform::current()->currentThread()->getWebTaskRunner()->postTask(BLINK_FROM_HERE, WTF::bind(&NotifyOnReaderCreationHelper::notify, m_factory.createWeakPtr(), WTF::unretained(client)));
+    taskRunner->postTask(BLINK_FROM_HERE, WTF::bind(&NotifyOnReaderCreationHelper::notify, m_factory.createWeakPtr(), WTF::unretained(client)));
 }
 
 void NotifyOnReaderCreationHelper::notify(WebDataConsumerHandle::Client* client)