Projects::CommitController#branches is slow

We seem to have a lot of slow queries here:

https://log.gitlab.net/goto/a076605a83cc66cd753b1d08a294eaee

Looks like it may be coming from the view timings?

https://log.gitlab.net/goto/4984577b55de8d911b8aba2bc6cb9bbf

Profiler shows most of the time spent in gRPC?

                      0.000      0.000      0.000      0.000              1/5     GRPC::ActiveCall#receive_and_check_status
                      0.000      0.000      0.000      0.000              1/5     GRPC::ActiveCall#server_streamer
                      0.005      0.005      0.000      0.000              1/5     GRPC::ActiveCall#request_response
                      6.809      4.146      2.663      0.000              2/5     GRPC::ActiveCall#remote_read
  92.63%  56.43%      6.814      4.151      2.663      0.000                5     GRPC::Core::Call#run_batch
                      0.000      0.000      0.000      0.000            7/733     Struct#initialize