[Paint Preview] Compile on official builds

Compile Paint Previews on official builds. This has already been
compiled/tested on trybots/waterfall for a long time so shouldn't cause
any issues. The goal is to get this code shipping so we can start some
experiments.

Binary-Size: Regression is known about and approved by agrieve@.
Bug: 1035118
Change-Id: I9ff9f053cf0149e2aa68eeea9e052eb5edd1293c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2067282Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Reviewed-by: Mehran Mahmoudi <mahmoudi@chromium.org>
Commit-Queue: Calder Kitagawa <ckitagawa@chromium.org>
Cr-Commit-Position: refs/heads/master@{#743303}

build/config/buildflags_paint_preview.gni

@@ -12,7 +12,5 @@ declare_args() {
   # Used by //components/paint_preview and //third_party/harfbuzz-ng.
   # TODO(bug/webrtc:11223) Move back this file in //components/paint_preview/
   #     once WebRTC doesn't roll harfbuzz-ng anymore, for consistency sake.
-  #     (Just revert the CL)
-  enable_paint_preview =
-      !is_chromecast && !is_ios && !is_fuchsia && !is_official_build
+  enable_paint_preview = !is_chromecast && !is_ios && !is_fuchsia
 }

components/paint_preview/browser/compositor_utils.cc

@@ -36,12 +36,7 @@ CreateCompositorCollection() {
   auto collection = content::ServiceProcessHost::Launch<
       mojom::PaintPreviewCompositorCollection>(
       content::ServiceProcessHost::Options()
-          // TODO(crbug/1035118): due to resource whitelisting, resources not
-          // shipped in production fail to compile into the resource pack. For
-          // now, the display name should be disabled until the buildflag hiding
-          // this feature is enabled for official builds.
-
-          // .WithDisplayName(IDS_PAINT_PREVIEW_COMPOSITOR_SERVICE_DISPLAY_NAME)
+          .WithDisplayName(IDS_PAINT_PREVIEW_COMPOSITOR_SERVICE_DISPLAY_NAME)
           .WithSandboxType(service_manager::SandboxType::kPrintCompositor)
           .Pass());
   mojo::PendingRemote<discardable_memory::mojom::DiscardableSharedMemoryManager>