Move Extension into extensions namespace

chrome/browser/chromeos/extensions/external_filesystem_apitest.cc

Index: chrome/browser/chromeos/extensions/external_filesystem_apitest.cc
diff --git a/chrome/browser/chromeos/extensions/external_filesystem_apitest.cc b/chrome/browser/chromeos/extensions/external_filesystem_apitest.cc
index 69ec32dc19063a3c2bb39f09c644c6e5c0512302..1ec43c696549c1b6133849e64099615c5ff9b60c 100644
--- a/chrome/browser/chromeos/extensions/external_filesystem_apitest.cc
+++ b/chrome/browser/chromeos/extensions/external_filesystem_apitest.cc
@@ -160,10 +160,11 @@ class FileSystemExtensionApiTest : public ExtensionApiTest {
 
   // Loads the extension, which temporarily starts the lazy background page
   // to dispatch the onInstalled event. We wait until it shuts down again.
-  const Extension* LoadExtensionAndWait(const std::string& test_name) {
+  const extensions::Extension* LoadExtensionAndWait(
+      const std::string& test_name) {
     BackgroundObserver page_complete;
     FilePath extdir = test_data_dir_.AppendASCII(test_name);
-    const Extension* extension = LoadExtension(extdir);
+    const extensions::Extension* extension = LoadExtension(extdir);
     if (extension)
       page_complete.WaitUntilClosed();
     return extension;