feat(force invert): force invert the entire app if its polarity is light

Instead of forcing dark each rendernode individually, we force invert
the entire app. This helps us avoid issues where some text or icons
don't get detected as dark, and they get inverted, causing black-on-
black text, etc.

By checking if the app is in light theme, and then inverting all the
RenderNodes indiscriminately, we have a much smaller chance of missing
some individual RenderNode.

This also disables the old force invert behavior even when the flag is
enabled. Force invert will supersede force dark if
android.view.accessibility.Flags.forceInvertColor is enabled.

Bug: 372558459
Flag: android.view.accessibility.force_invert_color
Test: manual: tested LinkedIn, Fitbit, Amazon

Change-Id: I296b7303b602938eee54d2e382a3c9dd4c4e9f15