From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Samuel Attard <sattard@salesforce.com>
Date: Mon, 6 Jun 2022 14:25:15 -0700
Subject: fix: allow guest webcontents to enter fullscreen

This can be upstreamed, a guest webcontents can't technically become the focused webContents. This DCHECK should allow all guest webContents to request fullscreen entrance.

diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 3fef597d18025bd35b4f7af105c6907602958223..a515cff65ec418ccd44bccd61b0cf8094cb864db 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -3714,7 +3714,7 @@ void WebContentsImpl::EnterFullscreenMode(
   OPTIONAL_TRACE_EVENT0("content", "WebContentsImpl::EnterFullscreenMode");
   DCHECK(CanEnterFullscreenMode(requesting_frame, options));
   DCHECK(requesting_frame->IsActive());
-  DCHECK(ContainsOrIsFocusedWebContents());
+  DCHECK(ContainsOrIsFocusedWebContents() || IsGuest());
 
   // When WebView is the `delegate_` we can end up with VisualProperties changes
   // synchronously. Notify the view ahead so it can handle the transition.