[EoS] Add APIs and tasks related to pulling images from the data store.

This patch:
* Adds APIs to ExploreSitesService that can request either a site image
  or a category image (which is a composite of multiple site images) as
  an SkBitmap (which is the format required for Java Bitmaps).
* Adds a task to fetch one or more images from the ExploreSitesStore,
  based on the site ID or category ID.
* The task filters based on the existence of an entry in the
  site_blacklist table (which is not populated yet but will be as a
  result of user long-press.

This DOES NOT implement conversion from byte vectors to SkBitmap (left
as a TODO.)

Bug: 867488
Change-Id: Id2e6a6abe2781b790f9ce3f597a9e747eddd4715
Reviewed-on: https://chromium-review.googlesource.com/1233176
Reviewed-by: Cathy Li <[email protected]>
Commit-Queue: Justin DeWitt <[email protected]>
Cr-Commit-Position: refs/heads/master@{#592501}
diff --git a/chrome/browser/BUILD.gn b/chrome/browser/BUILD.gn
index 7ee27cb8..b8df463 100644
--- a/chrome/browser/BUILD.gn
+++ b/chrome/browser/BUILD.gn
@@ -2151,6 +2151,8 @@
       "android/explore_sites/explore_sites_types.h",
       "android/explore_sites/get_catalog_task.cc",
       "android/explore_sites/get_catalog_task.h",
+      "android/explore_sites/get_images_task.cc",
+      "android/explore_sites/get_images_task.h",
       "android/explore_sites/import_catalog_task.cc",
       "android/explore_sites/import_catalog_task.h",
       "android/explore_sites/ntp_json_fetcher.cc",