Revert "support scroll backward to minus one screen via voice/switch access"

This reverts commit d5af944f41.

Reason for revert: Test failure on master that might be related to this code change.

Change-Id: I269bf5b0a6505da291e1ff4ed181a851268d6ed8

src/com/android/launcher3/Workspace.java

@@ -1034,13 +1034,6 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
         }
     }
 
-    @Override
-    protected boolean onOverscroll(int amount) {
-        // Enforce overscroll on -1 direction
-        if ((amount > 0 && !mIsRtl) || (amount < 0 && mIsRtl)) return false;
-        return super.onOverscroll(amount);
-    }
-
     @Override
     protected boolean shouldFlingForVelocity(int velocityX) {
         // When the overlay is moving, the fling or settle transition is controlled by the overlay.