Switch the status bar color earlier in the all apps transition

-> When LAUNCHER3_GRADIENT_ALL_APPS is true, switch the status / nav bar
   to be dark when the transition is 75% of the way through, since at this point
   the gradient is already substantially under the status bar.

issue 64385775

Change-Id: Ie27b8f2afa404c0b3081a4f17daa92ef4e0472bc

src/com/android/launcher3/allapps/AllAppsTransitionController.java

@@ -283,7 +283,9 @@ public class AllAppsTransitionController implements TouchController, VerticalPul
         }
 
         // Use a light system UI (dark icons) if all apps is behind at least half of the status bar.
-        boolean forceChange = shift <= mStatusBarHeight / 2;
+        boolean forceChange = FeatureFlags.LAUNCHER3_GRADIENT_ALL_APPS ?
+                shift <= mShiftRange / 4 :
+                shift <= mStatusBarHeight / 2;
         if (forceChange) {
             mLauncher.getSystemUiController().updateUiState(
                     SystemUiController.UI_STATE_ALL_APPS, !mIsDarkTheme);