How to refresh the parent window after opening a pop up window from inline page?

1 -> add a function in your inline page that executes window.parent.location=

function refreshParent(){
     window.parent.location='URL';
}

2 -> In the popup execute

window.opener.refreshParent()

rather than trying to refresh directly from the popup?

TO be be clear and precise the answer for this with sample code is below

<apex:page standardController="Account" extensions="Accountctrl">
<apex:form >
 <script>
  function openwindow(){
       window.open("/apex/pagereal", "myWindow", "width=200, height=100");
 }
  function navigate(){
  window.top.location.href='https://googleflowauth-dev-ed.my.salesforce.com/001900000096agv';//Parent function that redirects
  }
 </script>
<apex:pageBlock >
 <apex:pageBlockSection columns="1" id="Test" >
  <apex:inputcheckbox value="{!test.istest__c}" label="Same as Above">
    <apex:actionSupport event="onchange" rerender="Test" />
</apex:inputcheckbox>
<apex:outputPanel rendered="{!NOT(test.istest__c)}"> 
<apex:inputField value="{!test.Campaign__c}" />
<apex:inputField value="{!test.cust_vendor__c}" />
</apex:outputPanel>
   </apex:pageBlockSection> 
  </apex:pageBlock>

The code for popup will be as below

<apex:page >
 <!-- Begin Default Content REMOVE THIS -->
 <h1>Congratulations</h1>
 This is your new Page

  <script>

 function test(){
     alert('hello');
     window.opener.navigate();//call the parent function from child window and that does the trick
 }

 </script>
  <apex:form >
 <!-- End Default Content REMOVE THIS -->
  <apex:commandButton onclick="test()" value="Test"/>
  </apex:form>
</apex:page>