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This change starts using the new onError flow and checks if user visible is
supported. It does that by introducing a new method to the PushMessagingService that can be overriden by other vendors if they need to.

1) https://codereview.chromium.org/1130233003/
2) This CL
3) Cleanup CL where the empty onError method is removed and two new Layout tests
   are added so the exception is actually tested

BUG=479246

Review URL: https://codereview.chromium.org/1133083002

Cr-Commit-Position: refs/heads/master@{#329655}