GitLab

Skip imageloader RegisterComponent (component copy) in OnCustomInstall
and loads the copy in chrome.

Additions:
Add LoadComponentAtPath in ImageLoaderClient.
Save the (compatible) component path in browser_process.

BUG=chromium:780575
TEST=unittest; install/load component successfully.

Change-Id: Ic14f7d33ee6c8971dd6326f39fda546c94959e14
Reviewed-on: https://chromium-review.googlesource.com/801535Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
Reviewed-by: Joshua Pawlicki <waffles@chromium.org>
Commit-Queue: Xiaochu Liu <xiaochu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521622}