Implement improvements for request handling (issue #1327).

- Add a new CefRequestHandler::OnResourceResponse() method for inspecting the request/response headers and potentially restarting or redirecting the request.
- Add a new CefRequest::GetIdentifier() method for tracking a request across multiple CefRequestHandler callbacks.
- Pass a CefRequest object instead of just the old URL to CefRequestHandler::OnResourceRedirect().

git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@2073 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

include/cef_request.h

@@ -168,6 +168,14 @@ class CefRequest : public virtual CefBase {
   ///
   /*--cef(default_retval=TT_EXPLICIT)--*/
   virtual TransitionType GetTransitionType() =0;
+
+  ///
+  // Returns the globally unique identifier for this request or 0 if not
+  // specified. Can be used by CefRequestHandler implementations in the browser
+  // process to track a single request across multiple callbacks.
+  ///
+  /*--cef()--*/
+  virtual uint64 GetIdentifier() =0;
 };