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Ensures visibilitychange fires before pageshow to follow the spec at
https://html.spec.whatwg.org/multipage/browsing-the-web.html#session-history-document-visibility-change-steps

Also ensures we would fire visibiltychange after pagehide, consistent
with non-bfcache navigations.

(Current attempt to change the spec to fire visibilitychange before
pagehide is deemed to be a bit risky, see I2S:
https://groups.google.com/a/chromium.org/g/blink-dev/c/R7h6InVXzcI/m/FNSaab_GCAAJ)

TBR=altimin@chromium.org

Bug: 1133363
Change-Id: I2d99bffc8710deea6ca4e0de09544bf7f5218496
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2435142
Commit-Queue: Rakina Zata Amni <rakina@chromium.org>
Reviewed-by: Alexander Timin <altimin@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Yuzu Saijo <yuzus@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812066}