feat: add WebFrameMain detached property (#44209)

* feat: add WebFrameMain detached property

fix: throw instead of returning null senderFrame

test: detached frames

fix: ensure IPCs of pending deletion RFHs are dispatched

fix: lookup WFM by FTN ID to dispatch IPCs

feat: add frame.isDestroyed()

return null

fix: return undefined

docs: add null to all frame properties

refactor: option c, return null and emit warning

refactor: add routingId & processId to navigation events

test: null frame property

docs: clarify warning message

better wording

clarify null frame

fix: browserwindow spec

* maybe fix 🤷

* fix: use updated util #43722

* docs: add notice for frame change of behavior

* docs: clarify why frame properties may be null

* lint

* wip

* fix: content::FrameTreeNodeId lookup and converter

* refactor: avoid holey array deoptimization

---------

Co-authored-by: trop[bot] <37223003+trop[bot]@users.noreply.github.com>
Co-authored-by: Sam Maddock <smaddock@slack-corp.com>

lib/browser/guest-view-manager.ts

@@ -168,8 +168,8 @@ const createGuest = function (embedder: Electron.WebContents, embedderFrameId: n
     sendToEmbedder(IPC_MESSAGES.GUEST_VIEW_INTERNAL_DISPATCH_EVENT, 'will-frame-navigate', {
       url: event.url,
       isMainFrame: event.isMainFrame,
-      frameProcessId: event.frame.processId,
-      frameRoutingId: event.frame.routingId
+      frameProcessId: event.processId,
+      frameRoutingId: event.routingId
     });
   });