Have FrameFetchContext check for frame detached status more often.
Following r191022, a ResourceFetcher will no longer switch to a null
FetchContext upon it entering a frame-detached state, but continue to
call upon its FrameFetchContext in that state.
The latter wasn't fully prepared for being used in such a frame-less state,
so add the required checks.
R=mkwst@chromium.org
BUG=458222
Review URL: https://codereview.chromium.org/967893002
git-svn-id: svn://svn.chromium.org/blink/trunk@191045 bbb929c8-8fbe-4397-9dbb-9b2b20218538
2 files changed
