title: With animated transform,onLayout cannot be triggered
body: <p>My codes render a red square and moved using PanResponder.After release pan ,it move by animation transform.
  But onLayout() does not trigger when I drag the square.
  I want to get the square location anytime even in animating.
  What is the problem?</p>
  
  <pre><code>&lt;View style={styles.container}&gt;
      &lt;Animated.View
        style={[
          styles.box,
          {
            transform: [
              { translateX: this._animatedValue.x },
              { translateY: this._animatedValue.y },
            ],
            backgroundColor: 'red'
          },
        ]}
        {...this._panResponder.panHandlers}
        onLayout={({ nativeEvent }) =&gt; { console.log(nativeEvent.layout) }}
      /&gt;
    &lt;/View&gt;
  </code></pre>
  
  <p>Thanks!</p>