URLRequest::PrepareToRestart() call job_->Kill() and OrphanJob().

But OrphanJob() call job_->Kill() internally, so first Kill() call 
in PrepareToRestart() is not needed. 
This changelist remove the duplicated Kill() call. 

BUG=chromium:69937
TEST=pass net_unittests.

Patch provided by toyoshim@google.com.
Original review: http://codereview.chromium.org/6373002/


Review URL: http://codereview.chromium.org/6250021

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@72015 0039d316-1c4b-4281-b951-d872f2087c98

net/url_request/url_request.cc

@@ -490,7 +490,6 @@ void URLRequest::PrepareToRestart() {
   // one.
   net_log_.EndEvent(net::NetLog::TYPE_URL_REQUEST_START_JOB, NULL);
 
-  job_->Kill();
   OrphanJob();
 
   response_info_ = net::HttpResponseInfo();