Remove invalid check

extensions/browser/app_window/app_window.cc

Index: extensions/browser/app_window/app_window.cc
diff --git a/extensions/browser/app_window/app_window.cc b/extensions/browser/app_window/app_window.cc
index 67c5019fed46c095e8be287eeb014e22f6758626..0598549b7119478ec5767a8d0f8ebdd21b6dd3b6 100644
--- a/extensions/browser/app_window/app_window.cc
+++ b/extensions/browser/app_window/app_window.cc
@@ -484,7 +484,9 @@ void AppWindow::SetOnFirstCommitCallback(const base::Closure& callback) {
 }
 
 void AppWindow::OnReadyToCommitFirstNavigation() {
-  CHECK(content::IsBrowserSideNavigationEnabled());
+  if (!content::IsBrowserSideNavigationEnabled())

[Devlin, 2016/11/16 16:17:14]

Can we add a comment for why we only perform the work below
(WindowEventsReady(), calling on_first_commit_callback_) from here in the case
of plz navigate?

[clamy, 2016/11/17 14:07:41]

Done.

+    return;
+
   WindowEventsReady();
   if (on_first_commit_callback_.is_null())
     return;