GitLab

Rename some UserScriptLoader members to be a bit more clear.
- Rename "pending_load_" to "queued_load_". This better explains that a
  load is queued up, but not yet started.
- Rename "user_scripts_" to "loaded_scripts_". This more accurately
  indicates that the scripts contained within |loaded_scripts_| are the
  ones that have been fully loaded, rather than those that are queued
  up to load.

Also expose a UserScriptLoader getter on SharedUserScriptMaster, and
remove the forwarding method to UserScriptLoader::initial_load_complete.

Bug: None
Change-Id: I9276387a888572cf3e9575b5e2a2a1ee4dd47e07
Reviewed-on: https://chromium-review.googlesource.com/c/1387394Reviewed-by: Karan Bhatia <karandeepb@chromium.org>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#618364}