Adapt to the simplified GitReferenceUpdatedListener.Event API

Change-Id: Iaa077f0a4911aeed17873845903b812ca7183ea5
Signed-off-by: David Pursehouse <david.pursehouse@sonymobile.com>
diff --git a/src/main/java/com/googlesource/gerrit/plugins/branchnetwork/data/GitCommitCacheRefresh.java b/src/main/java/com/googlesource/gerrit/plugins/branchnetwork/data/GitCommitCacheRefresh.java
index 6675e13..9840bb2 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/branchnetwork/data/GitCommitCacheRefresh.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/branchnetwork/data/GitCommitCacheRefresh.java
@@ -46,11 +46,8 @@
 
   @Override
   public void onGitReferenceUpdated(GitReferenceUpdatedListener.Event event) {
-    for (Update update : event.getUpdates()) {
-      if (update.getRefName().startsWith("refs/heads")) {
-        networkGraphDataCache.refresh(event.getProjectName());
-        return;
-      }
+    if (event.getRefName().startsWith("refs/heads/")) {
+      networkGraphDataCache.refresh(event.getProjectName());
     }
   }
 }