title: Two way communication is returning error in Chrome Extension
body: <p>I am trying to send messages between <code>contentscript</code> and <code>background script</code> like below  </p>
  
  <p><b>ContentScript.js</b>  </p>
  
  <pre><code> chrome.extension.sendMessage({ type : "some" }, function(response) {
      anotherFunction( response.data );
      return true;        
   });
   function anotherFunction(data){
      // Some code here
      chrome.extension.sendMessage({ type : "someOther" }, function(response) {
           console.log( response.data ); // Failed to get Response
           return true;       
      });
   }
  </code></pre>
  
  <p><b>Background.js</b>  </p>
  
  <pre><code> chrome.extension.onMessage.addListener(function(request, sender, sendResponse) {
     switch(request.type){
         case "some":
              sendResponse({ data : "Some Response" });
              return true;
         break;
         case "someOther":
              // Here I am getting an error. Error is given below
              sendResponse({ data : "Some Response" });
         break;
     }
   });
  </code></pre>
  
  <p><b>Error</b><br>
   Could not send response: The chrome.runtime.onMessage listener must return true if you want to send a response after the listener returns </p>
  
  <p>How can I fix this issue.?</p>