Replace string16 with base::string16.

chrome/browser/autocomplete/extension_app_provider.h

Index: chrome/browser/autocomplete/extension_app_provider.h
diff --git a/chrome/browser/autocomplete/extension_app_provider.h b/chrome/browser/autocomplete/extension_app_provider.h
index 8202b4abe0f3d691a588f9fc5c56b25295d33e8d..5dbcc2638bb9259664955149f35bbe8642d5b234 100644
--- a/chrome/browser/autocomplete/extension_app_provider.h
+++ b/chrome/browser/autocomplete/extension_app_provider.h
@@ -46,10 +46,10 @@ class ExtensionAppProvider : public AutocompleteProvider,
   // eligible apps.
   struct ExtensionApp {
     // App's name.
-    string16 name;
+    base::string16 name;
     // App's launch URL (for platform apps, which don't have a launch URL, this
     // just points to the app's origin).
-    string16 launch_url;
+    base::string16 launch_url;
     // If false, then the launch_url will not be considered for matching,
     // not shown next to the match, and not displayed as the editable text if
     // the user selects the match with the arrow keys.