ResourceFetcher: Add POST support and the ability to set headers

content/public/renderer/resource_fetcher.h

Index: content/public/renderer/resource_fetcher.h
===================================================================
--- content/public/renderer/resource_fetcher.h	(revision 244609)
+++ content/public/renderer/resource_fetcher.h	(working copy)
@@ -36,17 +36,26 @@
   typedef base::Callback<void(const blink::WebURLResponse& response,
                               const std::string& data)> Callback;
 
-  // Creates a ResourceFetcher and starts fetching the specified resource.
-  // Caller takes ownership of the returned object.  Deleting the
-  // ResourceFetcher will cancel the request, and the callback will never be
-  // run.
-  static ResourceFetcher* Create(const GURL& url,
-                                 blink::WebFrame* frame,
-                                 blink::WebURLRequest::TargetType target_type,
-                                 const Callback& callback);
+  // Creates a ResourceFetcher for the specified resource.  Caller takes
+  // ownership of the returned object.  Deleting the ResourceFetcher will cancel
+  // the request, and the callback will never be run.
+  static ResourceFetcher* Create(const GURL& url);
 
+  // Set the corresponding parameters of the request.  Must be called before
+  // Start.  By default, requests are GETs with no body.
+  virtual void SetMethod(const std::string& method) = 0;
+  virtual void SetBody(const std::string& body) = 0;
+  virtual void SetHeader(const std::string& header,
+                         const std::string& value) = 0;
+
+  // Starts the request using the specified frame.  Calls |callback| when
+  // done.
+  virtual void Start(blink::WebFrame* frame,
+                     blink::WebURLRequest::TargetType target_type,
+                     const Callback& callback) = 0;
+
   // Sets how long to wait for the server to reply.  By default, there is no
-  // timeout.
+  // timeout.  Must be called after a request is started.
   virtual void SetTimeout(const base::TimeDelta& timeout) = 0;
 };