Remove RenderFrameHostImpl::subresource_loader_factories_bundle_ which is unused

This field was added before to keep the copy of the bundle around in
RFHI but not really used any more.

Bug: N/A
Change-Id: Ib007ee7dc941b980bab3ad92a1de016ad14d155c
Reviewed-on: https://chromium-review.googlesource.com/c/1365052
Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Commit-Queue: Kinuko Yasuda <kinuko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#614620}
2 files changed