Replace content::NavigationState public interface with some bools

Instead of exposing NavigationState, observers get two additional
values in Did{Start,Commit}ProvisionalLoad callbacks.

This will allow us to remove NavigationState entirely to simplify
navigation tracking between blink and content. As a first step,
we can stop tracking transition type.

[email protected],[email protected],[email protected],[email protected]

Bug: 855189
Change-Id: I6344ca4716121af9513c9bc672e5e9b28d49f055
Reviewed-on: https://chromium-review.googlesource.com/1226198
Commit-Queue: Dmitry Gozman <[email protected]>
Reviewed-by: Camille Lamy <[email protected]>
Cr-Commit-Position: refs/heads/master@{#592204}
48 files changed