Fix a crash due to contents being null

Bug: 911001
Change-Id: I72b6f8955be6c736f5c0063e76c3695bbde07e28
Reviewed-on: https://chromium-review.googlesource.com/c/1359128Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: rajendrant <rajendrant@chromium.org>
Cr-Commit-Position: refs/heads/master@{#613318}

chrome/browser/chrome_content_browser_client.cc

@@ -3208,7 +3208,7 @@ void ChromeContentBrowserClient::OverrideWebkitPrefs(
   web_prefs->lazy_load_enabled =
       (base::FeatureList::IsEnabled(features::kLazyFrameLoading) ||
        base::FeatureList::IsEnabled(features::kLazyImageLoading)) &&
-      (!contents->GetDelegate() ||
+      (!contents || !contents->GetDelegate() ||
        contents->GetDelegate()->ShouldAllowLazyLoad());
 
   if (base::FeatureList::IsEnabled(features::kLazyFrameLoading)) {