Correctly update frame load type after same-doc (history) navigation completion

For same document navigation the |FrameLoader::m_loadType| is set temporarily which means it gets
reset once load completes. This ensures we do not incorrectly attempt to restore scroll position
on content/frame size change once navigation is finished.


Review URL:

Cr-Commit-Position: refs/heads/master@{#369169}
4 files changed