Re-enable a test in the GCMClientImplTest

This test was disabled almost four years ago for unknown reasons and
passes fine on my machine. Let's see if the bots agree.

https://codereview.chromium.org/209293002

Change-Id: Id62e8c362b7b73861697ad1a82c0189471f60080
Reviewed-on: https://chromium-review.googlesource.com/891188
Reviewed-by: Anita Woodruff <[email protected]>
Commit-Queue: Peter Beverloo <[email protected]>
Cr-Commit-Position: refs/heads/master@{#540171}
1 file changed