Convert most geolocation layout tests to use a JS mock implementation.

third_party/WebKit/LayoutTests/fast/dom/Geolocation/script-tests/callback-to-deleted-context.js

 description("Tests that when a Geolocation request is made from a remote frame, and that frame's script context goes away before the Geolocation callback is made, the callback is made as usual.");
 
 function onFirstIframeLoaded() {
     iframe.src = 'resources/callback-to-deleted-context-inner2.html';
 }
 
 function onSecondIframeLoaded() {
     window.setTimeout(function() {
         testFailed('No callbacks invoked');
         finishJSTest();
     }, 500);
 }
 
 var iframe = document.createElement('iframe');
-iframe.src = 'resources/callback-to-deleted-context-inner1.html';
-document.body.appendChild(iframe);
+geolocationServiceMock.then(mock => {
+    mock.setGeolocationPermission(true);
+    mock.setGeolocationPosition(51.478, -0.166, 100);
+    iframe.src = 'resources/callback-to-deleted-context-inner1.html';
+    document.body.appendChild(iframe);
+});
 
 window.jsTestIsAsync = true;