Reland https://codereview.chromium.org/1271593002/ which was reverted

net/url_request/url_request_http_job_unittest.cc

Index: net/url_request/url_request_http_job_unittest.cc
diff --git a/net/url_request/url_request_http_job_unittest.cc b/net/url_request/url_request_http_job_unittest.cc
index 8df050202747c2ac1dab89c5248abd3b6ba52b34..96e82bf6ae46c830a13f36e5dbee293f765e98a1 100644
--- a/net/url_request/url_request_http_job_unittest.cc
+++ b/net/url_request/url_request_http_job_unittest.cc
@@ -391,26 +391,6 @@ TEST_F(URLRequestHttpJobTest, SetTransactionPriority) {
   EXPECT_EQ(HIGHEST, network_layer_.last_transaction()->priority());
 }
 
-// Make sure that URLRequestHttpJob passes on its priority updates to
-// newly-created transactions after the first one.
-TEST_F(URLRequestHttpJobTest, SetSubsequentTransactionPriority) {
-  scoped_refptr<TestURLRequestHttpJob> job(
-      new TestURLRequestHttpJob(req_.get()));
-  job->Start();
-
-  job->SetPriority(LOW);
-  ASSERT_TRUE(network_layer_.last_transaction());
-  EXPECT_EQ(LOW, network_layer_.last_transaction()->priority());
-
-  job->Kill();
-  network_layer_.ClearLastTransaction();
-
-  // Creates a second transaction.
-  job->Start();
-  ASSERT_TRUE(network_layer_.last_transaction());
-  EXPECT_EQ(LOW, network_layer_.last_transaction()->priority());
-}
-
 // Confirm we do advertise SDCH encoding in the case of a GET.
 TEST_F(URLRequestHttpJobTest, SdchAdvertisementGet) {
   EnableSdch();