Make it so that allow_js_access: false can be used with background pages created by window.open.

chrome/common/extensions/extension_manifest_constants.cc

Index: chrome/common/extensions/extension_manifest_constants.cc
diff --git a/chrome/common/extensions/extension_manifest_constants.cc b/chrome/common/extensions/extension_manifest_constants.cc
index d1fa89eea4aea30401ed018fbafc2817f11bc03f..a9cf15d5e30d3bba2f326f7de1cfcbb6dc52307d 100644
--- a/chrome/common/extensions/extension_manifest_constants.cc
+++ b/chrome/common/extensions/extension_manifest_constants.cc
@@ -180,9 +180,6 @@ const char kInvalidBackground[] =
     "Invalid value for 'background_page'.";
 const char kInvalidBackgroundAllowJsAccess[] =
     "Invalid value for 'background.allow_js_access'.";
-const char kInvalidBackgroundAllowJsAccessNoPage[] =
-    "Must specify one of background.page or background.scripts to use"
-    " background.allow_js_access.";
 const char kInvalidBackgroundCombination[] =
     "The background.page and background.scripts properties cannot be used at "
     "the same time.";