Allow URLFetcher to be used from sequenced tasks.

net/url_request/url_fetcher_core.h

Index: net/url_request/url_fetcher_core.h
diff --git a/net/url_request/url_fetcher_core.h b/net/url_request/url_fetcher_core.h
index 704697a1352ee9c906ce3b561e4f2e1894bc06fb..570c0f8e4148bb9924dbf3afa8cd7daad3083330 100644
--- a/net/url_request/url_fetcher_core.h
+++ b/net/url_request/url_fetcher_core.h
@@ -27,6 +27,7 @@
 #include "url/gurl.h"
 
 namespace base {
+class SequencedTaskRunner;
 class SingleThreadTaskRunner;
 }  // namespace base
 
@@ -216,10 +217,10 @@ class URLFetcherCore : public base::RefCountedThreadSafe<URLFetcherCore>,
 
   // Notify Delegate about the progress of upload/download.
   void InformDelegateUploadProgress();
-  void InformDelegateUploadProgressInDelegateThread(int64_t current,
-                                                    int64_t total);
+  void InformDelegateUploadProgressInDelegateSequence(int64_t current,
+                                                      int64_t total);
   void InformDelegateDownloadProgress();
-  void InformDelegateDownloadProgressInDelegateThread(
+  void InformDelegateDownloadProgressInDelegateSequence(
       int64_t current,
       int64_t total,
       int64_t current_network_bytes);
@@ -233,8 +234,8 @@ class URLFetcherCore : public base::RefCountedThreadSafe<URLFetcherCore>,
   URLFetcher::RequestType request_type_;  // What type of request is this?
   URLRequestStatus status_;          // Status of the request
   URLFetcherDelegate* delegate_;     // Object to notify on completion
-  // Task runner for the creating thread. Used to interact with the delegate.
-  scoped_refptr<base::SingleThreadTaskRunner> delegate_task_runner_;
+  // Task runner for the creating sequence. Used to interact with the delegate.
+  const scoped_refptr<base::SequencedTaskRunner> delegate_task_runner_;
   // Task runner for network operations.
   scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
   // Task runner for upload file access.