Fixed null pointer crash in ExtensionSettingsHandler.

chrome/browser/ui/webui/extensions/extension_settings_handler.cc

Index: chrome/browser/ui/webui/extensions/extension_settings_handler.cc
diff --git a/chrome/browser/ui/webui/extensions/extension_settings_handler.cc b/chrome/browser/ui/webui/extensions/extension_settings_handler.cc
index 5fbee8fbb2dafe5f6a1e9cfd993dd84588663dc7..275927ea8bba8daca51725e3d264d4a2861eae98 100644
--- a/chrome/browser/ui/webui/extensions/extension_settings_handler.cc
+++ b/chrome/browser/ui/webui/extensions/extension_settings_handler.cc
@@ -843,8 +843,10 @@ void ExtensionSettingsHandler::HandleEnableMessage(
 
   const Extension* extension =
       extension_service_->GetInstalledExtension(extension_id);
-  if (!extension ||
-      !management_policy_->UserMayModifySettings(extension, NULL)) {
+  if (!extension)
+    return;
+
+  if (!management_policy_->UserMayModifySettings(extension, NULL)) {
     LOG(ERROR) << "Attempt to enable an extension that is non-usermanagable was"
                << "made. Extension id: " << extension->id();
     return;