[cronet] Add mechanism for restarting CronetEnvironment

components/cronet/ios/test/start_cronet.h

Index: components/cronet/ios/test/start_cronet.h
diff --git a/components/cronet/ios/test/start_cronet.h b/components/cronet/ios/test/start_cronet.h
index e965c3e20c81b8a6c125a09d2d06b8e96060fbd4..47962b137012aa8be4c42860e8412dd8e2c5f6d4 100644
--- a/components/cronet/ios/test/start_cronet.h
+++ b/components/cronet/ios/test/start_cronet.h
@@ -4,8 +4,8 @@
 
 namespace cronet {
 
-// Starts Cronet if it hasn't already been started. Will always update Cronet
-// to point test.example.com" to "localhost:|port|".
-void StartCronetIfNecessary(int port);
+// Starts Cronet, or restarts if Cronet is already running.  Will have Cronet
+// point test.example.com" to "localhost:|port|".
+void StartCronet(int port);
 
 }  // namespace cronet