This CL aims at fixing the wallpaper parser logic so static categories
can be parsed properly from the XML file. This fix involves correctly
using the category builder which was earlier being used incorrectly
in case of null values of wallpaper.
Bug: 358363322
Test: Tested by building & installing picker on local and checking if
tiles are populated appropriately
Flag: com.android.wallpaper.refactor_wallpaper_category_flag
Change-Id: Id727f8b761adb39ce04b6330b5e55e941bff77ca
Bhavuk Jain
c6ae4f2f22