title: How to clear the external heap memory in flutter?
body: <p>Memory leak issue is there in my project.I need to resolve it.
  Initial memory is 15.7 MB and External memory is 79.2 KB
  <a href="https://i.stack.imgur.com/wdbe7.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/wdbe7.png" alt="enter image description here" /></a></p>
  <p>After performed some operation and clicked GC
  Final memory is 31.5 MB and external memory is 16.6 MB
  <a href="https://i.stack.imgur.com/MZbtd.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/MZbtd.png" alt="enter image description here" /></a></p>
  <p>Instance 6 in External memory having 7.92 MB.Could not find where it is stored in project.
  I clicked that instance 6 and it shows nothing.
  <a href="https://i.stack.imgur.com/QvDpF.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QvDpF.png" alt="enter image description here" /></a></p>
  <p>I need to clear that memory.But I have no idea to clear the external memory.Kindly help me to find the solution.</p>