Add a test that we resume commits after inserting the body.

Source/web/tests/sim/SimNetwork.h

Index: Source/web/tests/sim/SimNetwork.h
diff --git a/Source/web/tests/sim/SimNetwork.h b/Source/web/tests/sim/SimNetwork.h
new file mode 100644
index 0000000000000000000000000000000000000000..d95d4c62db47cad5d7ed8615a637853885890d2c
--- /dev/null
+++ b/Source/web/tests/sim/SimNetwork.h
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+// 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 SimNetwork_h
+#define SimNetwork_h
+
+#include "public/platform/WebURLLoaderTestDelegate.h"
+#include "wtf/HashMap.h"
+#include "wtf/text/StringHash.h"
+#include "wtf/text/WTFString.h"
+
+namespace blink {
+
+class SimRequest;
+class WebURLLoader;
+class WebURLLoaderClient;
+class WebURLResponse;
+
+class SimNetwork final : public WebURLLoaderTestDelegate {
+public:
+    SimNetwork();
+    ~SimNetwork();
+
+private:
+    friend class SimRequest;
+
+    static SimNetwork& current();
+
+    void servePendingRequests();
+    void addRequest(SimRequest&);
+    void removeRequest(SimRequest&);
+
+    // WebURLLoaderTestDelegate
+    void didReceiveResponse(WebURLLoaderClient*, WebURLLoader*, const WebURLResponse&) override;
+    void didReceiveData(WebURLLoaderClient*, WebURLLoader*, const char* data, int dataLength, int encodedDataLength) override;
+    void didFail(WebURLLoaderClient*, WebURLLoader*, const WebURLError&) override;
+    void didFinishLoading(WebURLLoaderClient*, WebURLLoader*, double finishTime, int64_t totalEncodedDataLength) override;
+
+    SimRequest* m_currentRequest;
+    HashMap<String, SimRequest*> m_requests;
+};
+
+} // namespace blink
+
+#endif