Adds cache lock timeout handling after finishing headers phase.

net/http/mock_http_cache.h

Index: net/http/mock_http_cache.h
diff --git a/net/http/mock_http_cache.h b/net/http/mock_http_cache.h
index 7718f35116974bb17bda26854341e77f7b93ba5f..ca0730429f7b401e18987acdf31a3859991b62f0 100644
--- a/net/http/mock_http_cache.h
+++ b/net/http/mock_http_cache.h
@@ -207,6 +207,9 @@ class MockHttpCache {
   // Wrapper to simulate cache lock timeout for new transactions.
   void SimulateCacheLockTimeout();
 
+  // Wrapper to simulate cache lock timeout for new transactions.
+  void SimulateCacheLockTimeoutAfterHeaders();
+
   // Wrapper to fail request conditionalization for new transactions.
   void FailConditionalizations();