Initialize TestNavigationObserver::last_navigation_type_ in ctor

With |TestNavigationObserver::last_navigation_type_| initialized properly, it's
possible to use TestNavigationObserver::last_navigation_type() to check whether
a navigation is still ongoing.

Change-Id: Ie814270d5e79bebb95e7ebea05c1ed7eb53bf88c
Reviewed-on: https://chromium-review.googlesource.com/c/1340813
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Wojciech Dzier┼╝anowski <wdzierzanowski@opera.com>
Cr-Commit-Position: refs/heads/master@{#609462}
1 file changed