[net] Better StopCaching() handling for HttpCache::Transaction.

net/http/disk_based_cert_cache_unittest.cc

Index: net/http/disk_based_cert_cache_unittest.cc
diff --git a/net/http/disk_based_cert_cache_unittest.cc b/net/http/disk_based_cert_cache_unittest.cc
index b2b640b300e6abf6a1623887a7e0c287e56ecc3c..e2c17c33c0839b64e0f347a4fd2284ffbcb067c5 100644
--- a/net/http/disk_based_cert_cache_unittest.cc
+++ b/net/http/disk_based_cert_cache_unittest.cc
@@ -44,9 +44,9 @@ const TestCertMetaData kCert2 = {
 // are irrelevant. Only one MockTransaction per certificate can be used
 // at a time.
 MockTransaction CreateMockTransaction(const char* key, int test_mode) {
-  MockTransaction transaction = {key,  "", base::Time(), "", LOAD_NORMAL,
-                                 "",   "", base::Time(), "", test_mode,
-                                 NULL, 0,  OK};
+  MockTransaction transaction = {
+      key,          "", base::Time(), "",      LOAD_NORMAL, "", "",
+      base::Time(), "", test_mode,    nullptr, nullptr,     0,  OK};
 
   return transaction;
 }