bundler: use right context
bundler: use right context

Used the stdlib context accidentally.

Change-Id: Idc1a593cba434c244d0fe34eeb042a3c057c2b86
Reviewed-on: https://code-review.googlesource.com/11375
Reviewed-by: Sarah Adams <2b342d1c32491b4e7587e4a0e291a5f0f95d4167@google.com>

googleapis/google-api-go-client,google/google-api-go-client,google/google-api-go-client,googleapis/google-api-go-client