Don't try to create extensionoptions for extensions that don't exist.

extensions/browser/guest_view/extension_options/extension_options_guest.cc

Index: extensions/browser/guest_view/extension_options/extension_options_guest.cc
diff --git a/extensions/browser/guest_view/extension_options/extension_options_guest.cc b/extensions/browser/guest_view/extension_options/extension_options_guest.cc
index ef79ee704918a5a009fff7995a441d0950e0be8f..66c9abae998af2bf8ffb0f96a1396f2f29df00c9 100644
--- a/extensions/browser/guest_view/extension_options/extension_options_guest.cc
+++ b/extensions/browser/guest_view/extension_options/extension_options_guest.cc
@@ -91,6 +91,13 @@ void ExtensionOptionsGuest::CreateWebContents(
       extensions::ExtensionRegistry::Get(browser_context());
   const extensions::Extension* extension =
       registry->enabled_extensions().GetByID(extension_id);
+  if (!extension) {
+    // The ID was valid but the extension didn't exist. Typically this will
+    // happen when an extension is disabled.
+    callback.Run(NULL);
+    return;
+  }
+
   options_page_ = extensions::OptionsPageInfo::GetOptionsPage(extension);
   if (!options_page_.is_valid()) {
     callback.Run(NULL);