Add option to change list item leading icon's background color

[LukasPaczos]

Task/Issue URL: https://app.asana.com/0/1202857801505092/1208848663479871

Description

Introduces an option to set a color for the list item leading icon's background. All leading icon backgrounds by default use a default grey-ish colors (depending on light/dark mode) with no option to change them. A new design for the Privacy Pro subscription activation screen requires the background for one of the list items to be specifically yellow.

I opted to provide this functionality by tinting the existing background drawable. This ensures that tinted background will still use the same shape as all the other list items, which cuts any additional maintenance if the background shapes/sizes get updated.

Steps to test this PR

You can try this out by applying below diff and navigating to Settings -> Sync & Backup:

diff --git a/sync/sync-impl/src/main/res/layout/view_sync_disabled.xml b/sync/sync-impl/src/main/res/layout/view_sync_disabled.xml
index d39d01829..0e0894019 100644
--- a/sync/sync-impl/src/main/res/layout/view_sync_disabled.xml
+++ b/sync/sync-impl/src/main/res/layout/view_sync_disabled.xml
@@ -36,6 +36,7 @@
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         app:leadingIconBackground="circular"
+        app:leadingIconBackgroundColor="@color/yellow10"
         app:leadingIcon="@drawable/ic_sync_device_all_24"
         app:primaryText="@string/sync_setup_with_another_device_cta_title"
         app:secondaryText="@string/sync_setup_with_another_device_cta_subtitle"/>

Before	After

UI changes

No changes to existing views.

[LukasPaczos]

Design idea has changed and this PR isn't needed at this time anymore.