PlzNavigate: Refactoring unit tests to use NavigationSimulator

Removed the usage of TestWebContents->DidNavigate variants in:
- render_frame_host_manager_unittest.cc
- devtools_manager_unittest.cc
- web_contents_impl_unittest.cc (derived only)

A CL will follow for base usage in web_contents_impl_unittest.cc
(~60 uses).

Bug: 728571
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_site_isolation
Change-Id: I600067df11875d31cbd9c5c1dab6a48f25e06843
Reviewed-on: https://chromium-review.googlesource.com/626063
Reviewed-by: Camille Lamy <clamy@chromium.org>
Commit-Queue: Arthur Hemery <ahemery@chromium.org>
Cr-Commit-Position: refs/heads/master@{#498442}
3 files changed