title: Flastlist moves to top every time after executing the 'onEndReached', if data is returned via 'Promis'
body: <p>While using 'Flastlist' component, when user scrolls down and 'onEndReached' fires, the 'Flastlist'
  loads data with out any issue, but it scroll back to the beginning of the list. This happens when extra rows are populated using 'Promis' while calling 'onEndReached'. If I returned row with out a 'Promis', it works fine.</p>
  
  <p>System:
    OS: Windows 10
    CPU: (4) x64 Intel(R) Pentium(R) CPU  N3540  @ 2.16GHz
    Memory: 2.95 GB / 7.89 GB
  Binaries:
    Yarn: 1.19.1 - C:\Program Files (x86)\Yarn\bin\yarn.CMD
    npm: 6.11.3 - C:\Program Files\nodejs\npm.CMD
  IDEs:
    Android Studio: Version  3.5.0.0 AI-191.8026.42.35.5900203</p>
  
  <p>I have uploaded the code here <a href="https://snack.expo.io/@sumeshcs1975/flatlist-onendreached" rel="nofollow noreferrer">https://snack.expo.io/@sumeshcs1975/flatlist-onendreached</a>
  Scroll down and when it reaches the end of screen, Flastlist scroll back automatically to the top</p>