Fix how rpc-server releases references after page reload

In addition to listening for "render-view-deleted", listen for
"ELECTRON_BROWSER_CONTEXT_RELEASE" synchronous message, which is sent by the
remote module when the page is about to be navigated.

This is required to allow child windows running in the same renderer to
correctly manage remote object references, since `render-view-deleted` is only
called when the renderer exits.

Close #9387

lib/browser/rpc-server.js

@@ -394,6 +394,11 @@ ipcMain.on('ELECTRON_BROWSER_DEREFERENCE', function (event, id) {
   objectsRegistry.remove(event.sender.getId(), id)
 })
 
+ipcMain.on('ELECTRON_BROWSER_CONTEXT_RELEASE', (e) => {
+  objectsRegistry.clear(e.sender.getId())
+  e.returnValue = null
+})
+
 ipcMain.on('ELECTRON_BROWSER_GUEST_WEB_CONTENTS', function (event, guestInstanceId) {
   try {
     let guestViewManager = require('./guest-view-manager')

lib/renderer/api/remote.js

@@ -304,6 +304,10 @@ ipcRenderer.on('ELECTRON_RENDERER_RELEASE_CALLBACK', function (event, id) {
   callbacksRegistry.remove(id)
 })
 
+process.on('exit', () => {
+  ipcRenderer.sendSync('ELECTRON_BROWSER_CONTEXT_RELEASE')
+})
+
 // Get remote module.
 exports.require = function (module) {
   return metaToValue(ipcRenderer.sendSync('ELECTRON_BROWSER_REQUIRE', module))