Update overflowInset flag to use public static field

Summary: There's no need to use private feature flag for overflowInset feature. This makes future refactor on feature flags easier.

Reviewed By: javache

Differential Revision: D35866302

fbshipit-source-id: a3fde212ff40cd6d4c68832bb39b34de5a17a8d4

ReactAndroid/src/main/java/com/facebook/react/uimanager/TouchTargetHelper.java

@@ -192,7 +192,7 @@ public class TouchTargetHelper {
           // If the touch point is outside of the overflowinset for the view, we can safely ignore
           // it.
           if (ViewUtil.getUIManagerType(view.getId()) == FABRIC
-              && ReactFeatureFlags.doesUseOverflowInset()
+              && ReactFeatureFlags.useOverflowInset
               && !isTouchPointInViewWithOverflowInset(eventCoords[0], eventCoords[1], view)) {
             return null;
           }