mojo: Use stl utilities from the base namespace

mojo/public/cpp/bindings/lib/interface_endpoint_client.cc

Index: mojo/public/cpp/bindings/lib/interface_endpoint_client.cc
diff --git a/mojo/public/cpp/bindings/lib/interface_endpoint_client.cc b/mojo/public/cpp/bindings/lib/interface_endpoint_client.cc
index 9ececaa79863bd798f634f257437d77a9082539e..523c75ebc229d7a463584df6648f0b4cbe5c5a51 100644
--- a/mojo/public/cpp/bindings/lib/interface_endpoint_client.cc
+++ b/mojo/public/cpp/bindings/lib/interface_endpoint_client.cc
@@ -242,7 +242,7 @@ bool InterfaceEndpointClient::AcceptWithResponder(Message* message,
   controller_->SyncWatch(&response_received);
   // Make sure that this instance hasn't been destroyed.
   if (weak_self) {
-    DCHECK(ContainsKey(sync_responses_, request_id));
+    DCHECK(base::ContainsKey(sync_responses_, request_id));
     auto iter = sync_responses_.find(request_id);
     DCHECK_EQ(&response_received, iter->second->response_received);
     if (response_received) {