Don't preserve NavigationEntry for failed navigations with invalid URLs.

The formatting logic may rewrite such URLs into an unsafe state.  This
is a first step before preventing navigations to invalid URLs entirely.

Bug: 850824
Change-Id: I71743bfb4b610d55ce901ee8902125f934a2bb23
Reviewed-on: https://chromium-review.googlesource.com/c/1252942
Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Commit-Queue: Charlie Reis <creis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#597304}