commit 3d76aaf8edee4eee6b6a04efa165a06bd9307372
author Dmitry Gozman <dgozman@chromium.org> Fri Mar 22 22:05:27 2019
committer Commit Bot <commit-bot@chromium.org> Fri Mar 22 22:05:27 2019
tree 45e5e1636e3a508ff54c7935cd80083e6463ef52
parent 5593416f75747b3a431d64636fad7e7bde061625

DocumentLoader: handle various failing situations upfront

Instead of figuring out that we should not load somewhere in
the middle of the process, we introduce PrepareForLoad() method
and make StartLoading always commit navigation.

This will make it possible to remove provisional document loader.

Drive-by: fixed a bug where SetMixedAutoupgradeOptOut was called
on a wrong document, but the test was failing to load a document
and did not catch that.

Bug: 855189
Change-Id: I2abb16b616b32fa67494425a7a81dc91e5905818
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1535180
Commit-Queue: Dmitry Gozman <dgozman@chromium.org>
Reviewed-by: Nate Chapin <japhet@chromium.org>
Cr-Commit-Position: refs/heads/master@{#643570}