GitLab

Remove a block of code that used to detect a incorrect PageTransition
and to replace it by its correct value.
Apparently, this block is no more reached. This CL removes it.
Furthermore, a test is added. It replays the steps one had to do to
reach this block of code.

BUG=736772,740461
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Review-Url: https://codereview.chromium.org/2961903003
Cr-Commit-Position: refs/heads/master@{#485287}