NumberPicker cannot fling in scrollable containers.

1. NumberPicker was not preventing its predecessor from
   intercepting touch events that are on top of it, hence
   it was not flingable in scrollable containres.

bug:5661117

Change-Id: I145f59b069f479935f551bc5e841f13468a6c676

Author: sganov

core/java/android/widget/NumberPicker.java

@@ -771,6 +771,8 @@ public boolean onInterceptTouchEvent(MotionEvent event) {
                 mLastDownEventTime = event.getEventTime();
                 mIngonreMoveEvents = false;
                 mShowSoftInputOnTap = false;
+                // Make sure we wupport flinging inside scrollables.
+                getParent().requestDisallowInterceptTouchEvent(true);
                 if (!mFlingScroller.isFinished()) {
                     mFlingScroller.forceFinished(true);
                     mAdjustScroller.forceFinished(true);