Add FetchDataConsumerHandle and utility functions/classes

Source/modules/fetch/DataConsumerHandleTestUtil.h

Index: Source/modules/fetch/DataConsumerHandleTestUtil.h
diff --git a/Source/modules/fetch/DataConsumerHandleTestUtil.h b/Source/modules/fetch/DataConsumerHandleTestUtil.h
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index 0000000000000000000000000000000000000000..30d71137c8db6ddf27e1a98f1fd283158c047ad1
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+++ b/Source/modules/fetch/DataConsumerHandleTestUtil.h
@@ -0,0 +1,178 @@
+// Copyright 2015 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 DataConsumerHandleTestUtil_h
+#define DataConsumerHandleTestUtil_h
+
+#include "modules/fetch/DataConsumerHandleUtil.h"
+#include "modules/fetch/FetchDataConsumerHandle.h"
+#include "platform/Task.h"
+#include "platform/ThreadSafeFunctional.h"
+#include "platform/heap/Handle.h"
+#include "public/platform/Platform.h"
+#include "public/platform/WebDataConsumerHandle.h"
+#include "public/platform/WebThread.h"
+#include "public/platform/WebTraceLocation.h"
+#include "public/platform/WebWaitableEvent.h"
+#include "wtf/Locker.h"
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+namespace blink {
+
+class DataConsumerHandleTestUtil {
+public:
+    class NoopClient final : public WebDataConsumerHandle::Client {
+    public:
+        void didGetReadable() override { }
+    };
+
+    class ThreadingTestBase : public ThreadSafeRefCounted<ThreadingTestBase> {
+    public:
+        class Context : public ThreadSafeRefCounted<Context> {
+        public:
+            static PassRefPtr<Context> create() { return adoptRef(new Context); }
+            void recordAttach(const String& handle)
+            {
+                MutexLocker locker(m_loggingMutex);
+                m_result.append("A reader is attached to " + handle + " on " + currentThreadName() + ".\n");
+            }
+            void recordDetach(const String& handle)
+            {
+                MutexLocker locker(m_loggingMutex);
+                m_result.append("A reader is detached from " + handle + " on " + currentThreadName() + ".\n");
+            }
+
+            const String& result()
+            {
+                MutexLocker locker(m_loggingMutex);
+                return m_result;
+            }
+            WebThread* readingThread() { return m_readingThread.get(); }
+            WebThread* updatingThread() { return m_updatingThread.get(); }
+
+        private:
+            Context()
+                : m_readingThread(adoptPtr(Platform::current()->createThread("reading thread")))
+                , m_updatingThread(adoptPtr(Platform::current()->createThread("updating thread")))
+            {
+            }
+            String currentThreadName()
+            {
+                if (m_readingThread->isCurrentThread())
+                    return "the reading thread";
+                if (m_updatingThread->isCurrentThread())
+                    return "the updating thread";
+                return "an unknown thread";
+            }
+
+            OwnPtr<WebThread> m_readingThread;
+            OwnPtr<WebThread> m_updatingThread;
+            Mutex m_loggingMutex;
+            String m_result;
+        };
+
+        class ReaderImpl final : public WebDataConsumerHandle::Reader {
+        public:
+            ReaderImpl(const String& name, PassRefPtr<Context> context) : m_name(name.isolatedCopy()), m_context(context)
+            {
+                m_context->recordAttach(m_name.isolatedCopy());
+            }
+            ~ReaderImpl() override { m_context->recordDetach(m_name.isolatedCopy()); }
+
+            using Result = WebDataConsumerHandle::Result;
+            using Flags = WebDataConsumerHandle::Flags;
+            Result read(void*, size_t, Flags, size_t*) override { return WebDataConsumerHandle::ShouldWait; }
+            Result beginRead(const void**, Flags, size_t*) override { return WebDataConsumerHandle::ShouldWait; }
+            Result endRead(size_t) override { return WebDataConsumerHandle::UnexpectedError; }
+
+        private:
+            const String m_name;
+            RefPtr<Context> m_context;
+        };
+        class DataConsumerHandle final : public WebDataConsumerHandle {
+        public:
+            DataConsumerHandle(const String& name, PassRefPtr<Context> context) : m_name(name.isolatedCopy()), m_context(context) { }
+
+        private:
+            Reader* obtainReaderInternal(Client*) { return new ReaderImpl(m_name, m_context); }
+            const String m_name;
+            RefPtr<Context> m_context;
+        };
+
+        void resetReader() { m_reader = nullptr; }
+        void signalDone() { m_waitableEvent->signal(); }
+        const String& result() { return m_context->result(); }
+        WebThread* readingThread() { return m_context->readingThread(); }
+        WebThread* updatingThread() { return m_context->updatingThread(); }
+
+    protected:
+        RefPtr<Context> m_context;
+        OwnPtr<WebDataConsumerHandle::Reader> m_reader;
+        OwnPtr<WebWaitableEvent> m_waitableEvent;
+        NoopClient m_client;
+    };
+
+    class ThreadingHandleNotificationTest : public ThreadingTestBase, public WebDataConsumerHandle::Client {
+    public:
+        using Self = ThreadingHandleNotificationTest;
+        void run(PassOwnPtr<WebDataConsumerHandle> handle)
+        {
+            m_context = Context::create();
+            m_waitableEvent = adoptPtr(Platform::current()->createWaitableEvent());
+            m_handle = handle;
+
+            readingThread()->postTask(FROM_HERE, new Task(threadSafeBind(&Self::obtainReader, this)));
+
+            m_waitableEvent->wait();
+        }
+
+    private:
+        void obtainReader()
+        {
+            m_reader = m_handle->obtainReader(this);
+        }
+        void didGetReadable() override
+        {
+            readingThread()->postTask(FROM_HERE, new Task(threadSafeBind(&Self::resetReader, this)));
+            readingThread()->postTask(FROM_HERE, new Task(threadSafeBind(&Self::signalDone, this)));
+        }
+
+        OwnPtr<WebDataConsumerHandle> m_handle;
+    };
+
+    class ThreadingHandleNoNotificationTest : public ThreadingTestBase, public WebDataConsumerHandle::Client {
+    public:
+        using Self = ThreadingHandleNoNotificationTest;
+        void run(PassOwnPtr<WebDataConsumerHandle> handle)
+        {
+            m_context = Context::create();
+            m_waitableEvent = adoptPtr(Platform::current()->createWaitableEvent());
+            m_handle = handle;
+
+            readingThread()->postTask(FROM_HERE, new Task(threadSafeBind(&Self::obtainReader, this)));
+
+            m_waitableEvent->wait();
+        }
+
+    private:
+        void obtainReader()
+        {
+            m_reader = m_handle->obtainReader(this);
+            m_reader = nullptr;
+            readingThread()->postTask(FROM_HERE, new Task(threadSafeBind(&Self::signalDone, this)));
+        }
+        void didGetReadable() override
+        {
+            ASSERT_NOT_REACHED();
+        }
+
+        OwnPtr<WebDataConsumerHandle> m_handle;
+    };
+};
+
+} // namespace blink
+
+#endif // DataConsumerHandleTestUtil_h