Fix default apps losing the "bookmark app" bit once they get updated.

chrome/browser/extensions/external_extension_provider_interface.h

Index: chrome/browser/extensions/external_extension_provider_interface.h
diff --git a/chrome/browser/extensions/external_extension_provider_interface.h b/chrome/browser/extensions/external_extension_provider_interface.h
index 03951eccfe89e014e7b8620b064c232c1b1e5211..ce51e0e0b084f2e0d2a4eeacfcae2d4602a92e91 100644
--- a/chrome/browser/extensions/external_extension_provider_interface.h
+++ b/chrome/browser/extensions/external_extension_provider_interface.h
@@ -80,6 +80,10 @@ class ExternalExtensionProviderInterface {
   // Determines if this provider had loaded the list of external extensions
   // from its source.
   virtual bool IsReady() const = 0;
+
+  // The creation flags that the provider passes to
+  // OnExternalExtensionFileFound.
+  virtual int GetCreationFlags() const = 0;
 };
 
 typedef std::vector<linked_ptr<ExternalExtensionProviderInterface> >