Only log SSL cert error histograms for successful page loads.

Otherwise navigating to https://doesnt-exit.com or possible captive error pages would get incorrectly flagged in the stats.

Bug=740336

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_site_isolation
Change-Id: Id170382d3407d21f502b9d71fb6245c69fa2f0a9
Reviewed-on: https://chromium-review.googlesource.com/656017
Commit-Queue: Emily Stark <[email protected]>
Reviewed-by: Emily Stark <[email protected]>
Cr-Commit-Position: refs/heads/master@{#500447}
1 file changed