Bug 1764790 - Remove TopLevelNavigationDelegate support. r=nika

Depends on D143926

Differential Revision: https://phabricator.services.mozilla.com/D143927

docshell/base/nsDocShell.cpp

@@ -9448,23 +9448,6 @@ nsresult nsDocShell::InternalLoad(nsDocShellLoadState* aLoadState,
     return rv;
   }
 
-  if (mBrowsingContext->IsTopContent() &&
-      !aLoadState->GetPendingRedirectedChannel()) {
-    nsCOMPtr<nsITopLevelNavigationDelegate> delegate =
-        do_GetInterface(mTreeOwner);
-    if (delegate) {
-      bool shouldNavigate = false;
-      nsIReferrerInfo* referrerInfo = aLoadState->GetReferrerInfo();
-      rv = delegate->ShouldNavigate(
-          this, aLoadState->URI(), aLoadState->LoadType(), referrerInfo,
-          !!aLoadState->PostDataStream(), aLoadState->TriggeringPrincipal(),
-          aLoadState->Csp(), &shouldNavigate);
-      if (NS_SUCCEEDED(rv) && !shouldNavigate) {
-        return NS_OK;
-      }
-    }
-  }
-
   // mContentViewer->PermitUnload can destroy |this| docShell, which
   // causes the next call of CanSavePresentation to crash.
   // Hold onto |this| until we return, to prevent a crash from happening.