[Sync] Update Type Info section of sync-internals.

components/sync/engine/model_safe_worker.cc

Index: components/sync/engine/model_safe_worker.cc
diff --git a/components/sync/engine/model_safe_worker.cc b/components/sync/engine/model_safe_worker.cc
index 773571675ba7806755af26c9d2ab6b1b7bec18f6..bd2ac21b8e7486c29f5c79b02665cd02e704e8e1 100644
--- a/components/sync/engine/model_safe_worker.cc
+++ b/components/sync/engine/model_safe_worker.cc
@@ -53,23 +53,22 @@ ModelSafeGroup GetGroupForModelType(const ModelType type,
 std::string ModelSafeGroupToString(ModelSafeGroup group) {
   switch (group) {
     case GROUP_UI:
-      return "GROUP_UI";
+      return "Group UI";
     case GROUP_DB:
-      return "GROUP_DB";
+      return "Group DB";
     case GROUP_FILE:
-      return "GROUP_FILE";
+      return "Group File";
     case GROUP_HISTORY:
-      return "GROUP_HISTORY";
+      return "Group History";
     case GROUP_PASSIVE:
-      return "GROUP_PASSIVE";
+      return "Group Passive";
     case GROUP_PASSWORD:
-      return "GROUP_PASSWORD";
+      return "Group Password";
     case GROUP_NON_BLOCKING:
-      return "GROUP_NON_BLOCKING";
-    default:
-      NOTREACHED();
-      return "INVALID";
+      return "Group Non Blocking";
   }
+  NOTREACHED();
+  return "Invalid";
 }
 
 ModelSafeWorker::ModelSafeWorker()