Mojo bindings: merge the control messages of sending disconnect reason and notifying endpoint close…

mojo/public/cpp/bindings/associated_binding.h

Index: mojo/public/cpp/bindings/associated_binding.h
diff --git a/mojo/public/cpp/bindings/associated_binding.h b/mojo/public/cpp/bindings/associated_binding.h
index 5c3764f5ee672b1518409cab20e80809a5ca3b2e..0a95da430e54ebb8b7d8f95fb4e669311b7fb0b4 100644
--- a/mojo/public/cpp/bindings/associated_binding.h
+++ b/mojo/public/cpp/bindings/associated_binding.h
@@ -127,15 +127,13 @@ class AssociatedBinding {
   // Closes the associated interface. Puts this object into a state where it can
   // be rebound.
   void Close() {
-    DCHECK(endpoint_client_);
     endpoint_client_.reset();
   }
 
   // Similar to the method above, but also specifies a disconnect reason.
   void CloseWithReason(uint32_t custom_reason, const std::string& description) {
-    DCHECK(endpoint_client_);
-    endpoint_client_->control_message_proxy()->SendDisconnectReason(
-        custom_reason, description);
+    if (endpoint_client_)
+      endpoint_client_->CloseWithReason(custom_reason, description);
     Close();
   }