Correct colors for icons in "Search settings" for dark theme

Create a themed app context with theme from R.style.Theme_Settings.
After that create a context with theme from themed app context
before getting the drawable from the package.

Bug: 139695450
Test: Manual - set dark theme and search for 'media volume'
      in settings. The icon should be visible
Change-Id: I40ea745046074ddd80c01cb35ebaf566ffa80b74