Adds bluetooth connection type to NetworkChangeNotifier.

net/tools/net_watcher/net_watcher.cc

Index: net/tools/net_watcher/net_watcher.cc
diff --git a/net/tools/net_watcher/net_watcher.cc b/net/tools/net_watcher/net_watcher.cc
index e5582609e744af0799d01684ded47014055ccd74..51441bfb1b9a8eb0bd9b595127cb3b8d0b82d0b7 100644
--- a/net/tools/net_watcher/net_watcher.cc
+++ b/net/tools/net_watcher/net_watcher.cc
@@ -50,8 +50,8 @@ const char* ConnectionTypeToString(
       return "CONNECTION_4G";
     case net::NetworkChangeNotifier::CONNECTION_NONE:
       return "CONNECTION_NONE";
-    default:
-      return "CONNECTION_UNEXPECTED";
+    case net::NetworkChangeNotifier::CONNECTION_BLUETOOTH:
+      return "CONNECTION_BLUETOOTH";
   }
 }