Populate colors resources for Material color scheme

Test: adb shell settings put secure \
        theme_customization_overlay_packages \
'''\{\
\"android.theme.customization.system_palette\":\"fff000\",\
\"android.theme.customization.color_source\":\"home_wallpaper\",\
\"android.theme.customization.theme_style\":\"RAINBOW\"\}\
''' # Or EXPRESSIVE, SPRITZ, TONAL_SPOT, FRUIT_SALAD, VIBRANT, or
    # MONOCHROMATIC
Test: adb shell settings put secure contrast_level 0 # or 0.5, or 1
Test: atest SystemUITests
Bug: 266484809

Change-Id: Icab77a2334bd40036d647c357d5c97f1f71cf74c