Update references to the extension messaging APIs to point to the "runtime"

chrome/test/data/extensions/management/launch_app/test.js

Index: chrome/test/data/extensions/management/launch_app/test.js
diff --git a/chrome/test/data/extensions/management/launch_app/test.js b/chrome/test/data/extensions/management/launch_app/test.js
index 3f42c1650b19c3840bb84c2f3e319c1685e310fc..468db74ad4687c502a9d12f28b2c7b335a567407 100644
--- a/chrome/test/data/extensions/management/launch_app/test.js
+++ b/chrome/test/data/extensions/management/launch_app/test.js
@@ -13,8 +13,8 @@ window.onload = function() {
         // Try launching a non-app extension, which should fail.
         var expected_error = "Extension " + item.id + " is not an App";
         chrome.management.launchApp(item.id, function() {
-          if (chrome.extension.lastError &&
-              chrome.extension.lastError.message == expected_error) {
+          if (chrome.runtime.lastError &&
+              chrome.runtime.lastError.message == expected_error) {
             chrome.test.sendMessage("got_expected_error");
           }
         });