Add HttpProtocolHandler and convert everything to use it

net/url_request/url_request_job_manager.h

Index: net/url_request/url_request_job_manager.h
diff --git a/net/url_request/url_request_job_manager.h b/net/url_request/url_request_job_manager.h
index ab67c8a987651cf1062c576d42009a5c09d44211..ac382e39e2ec1ce2648d8a4dcc62441ade36099f 100644
--- a/net/url_request/url_request_job_manager.h
+++ b/net/url_request/url_request_job_manager.h
@@ -50,9 +50,6 @@ class NET_EXPORT URLRequestJobManager {
   URLRequestJob* MaybeInterceptResponse(
       URLRequest* request, NetworkDelegate* network_delegate) const;
 
-  // Returns true if the manager has a built-in handler for |scheme|.
-  static bool SupportsScheme(const std::string& scheme);
-
  private:
   friend struct base::DefaultSingletonTraits<URLRequestJobManager>;