Use FilterContext to allow filters to access URLRequestJob data...

chrome/browser/dom_ui/chrome_url_data_manager.cc

Index: chrome/browser/dom_ui/chrome_url_data_manager.cc
===================================================================
--- chrome/browser/dom_ui/chrome_url_data_manager.cc	(revision 11030)
+++ chrome/browser/dom_ui/chrome_url_data_manager.cc	(working copy)
@@ -43,7 +43,7 @@
   virtual void Start();
   virtual void Kill();
   virtual bool ReadRawData(net::IOBuffer* buf, int buf_size, int *bytes_read);
-  virtual bool GetMimeType(std::string* mime_type);
+  virtual bool GetMimeType(std::string* mime_type) const;
 
   // Called by ChromeURLDataManager to notify us that the data blob is ready
   // for us.
@@ -278,7 +278,7 @@
   chrome_url_data_manager.RemoveRequest(this);
 }
 
-bool URLRequestChromeJob::GetMimeType(std::string* mime_type) {
+bool URLRequestChromeJob::GetMimeType(std::string* mime_type) const {
   *mime_type = mime_type_;
   return !mime_type_.empty();
 }