change protocol buffer compiler options in channel_common.proto

git-svn-id: http://google-cache-invalidation-api.googlecode.com/svn/trunk/src@329 1cc9d426-c294-39be-ba72-c0199ca0f247
diff --git a/google/cacheinvalidation/channel_common.proto b/google/cacheinvalidation/channel_common.proto
index 2c51591..58e73be 100644
--- a/google/cacheinvalidation/channel_common.proto
+++ b/google/cacheinvalidation/channel_common.proto
@@ -17,9 +17,9 @@
 
 syntax = "proto2";
 
-package ipc.invalidation;
+option optimize_for = LITE_RUNTIME;
 
-option cc_api_version = 2;
+package ipc.invalidation;
 
 message ChannelMessageEncoding {
     // What kind of encoding is used for network_message