Let certain apps go edge-to-edge by default

This CL adds an integer system property which is an SDK version that if
an app targets that version or above, the app will go edge-to-edge by
default. This gives the app developer a chance to preview what their UI
will look like if the edge-to-edge policy for apps is forcibly enabled.

To make the app go edge-to-edge by default, this CL changes the
following default values:
1. mDecorFitsSystemWindows. The new default value is false.
   See: Window#setDecorFitsSystemWindows
2. mStatusBarColor. The new default color is transparent.
   See: Window#setStatusBarColor
3. mNavigationBarColor. The new default color is transparent.
   See: Window#setNavigationBarColor

Bug: 309578419
Test: manual
Change-Id: Ieeb27b0c6c1bda42dbb06d0babc6473817c98bfc