ResourceLoader: Fix a bunch of double-cancellation/double-error notification cases.

net/url_request/url_request_job.h

Index: net/url_request/url_request_job.h
diff --git a/net/url_request/url_request_job.h b/net/url_request/url_request_job.h
index 610ce3323e6ea3bf2bc905194d78fe974275a572..20438cb2e2c1c0a6c49174d651bfec8ee2c53c0c 100644
--- a/net/url_request/url_request_job.h
+++ b/net/url_request/url_request_job.h
@@ -360,15 +360,18 @@ class NET_EXPORT URLRequestJob : public base::PowerObserver {
   // |bytes_read| unfiltered bytes have been read for this job.
   void RecordBytesRead(int bytes_read);
 
-  // NotifyDone marks that request is done. It is really a glorified
+  // OnDone marks that request is done. It is really a glorified
   // set_status, but also does internal state checking and job tracking. It
   // should be called once per request, when the job is finished doing all IO.
-  void NotifyDone(const URLRequestStatus& status);
-
-  // Some work performed by NotifyDone must be completed asynchronously so
-  // as to avoid re-entering URLRequest::Delegate. This method performs that
-  // work.
-  void CompleteNotifyDone();
+  //
+  // If |notify_done| is true, will notify the URLRequest of completion.

[Randy Smith (Not in Mondays), 2016/12/06 23:44:43]

I believe this is only done if the completion is in error.   The non-error
completion looks to be done through NotifyReadCompleted directly (from
SourceStreamReadComplete).

[mmenke, 2016/12/07 16:17:15]

Done.

+  // Otherwise, the caller will need to do this itself, possibly through a
+  // synchronous return value.
+  void OnDone(const URLRequestStatus& status, bool notify_done);
+
+  // Takes care of the notification initiated by OnDone() to avoid re-entering
+  // the URLRequest::Delegate.

[Randy Smith (Not in Mondays), 2016/12/06 23:44:43]

I think some gesture to the PostTask or the asynchronous triggering of this
method by OnDone() belongs in this comment.

[mmenke, 2016/12/07 16:17:15]

Done.

+  void NotifyDone();
 
   // Subclasses may implement this method to record packet arrival times.
   // The default implementation does nothing.  Only invoked when bytes have been