Remove ResourceContext from PluginService

This switches to using BrowserContext instead of ResourceContext for
PluginService and plugin_utils.cc. This required moving
PluginRegistryImpl, PluginInfoHostImpl, and
RenderFrameMessageFilter::OnGetPluginInfo to run on the UI thread.

This eliminates one of the major dependencies of extensions::InfoMap.

Bug: 980774
Change-Id: I7b26c5b40dc8b98c518339b771249ef16e6ec856
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1730093
Commit-Queue: Clark DuVall <[email protected]>
Reviewed-by: John Abd-El-Malek <[email protected]>
Cr-Commit-Position: refs/heads/master@{#684082}
51 files changed