Add Throbber control for DOMUI. Use it everywhere in options and in Sync setup UI.

chrome/browser/dom_ui/shared_resources_data_source.cc

Index: chrome/browser/dom_ui/shared_resources_data_source.cc
diff --git a/chrome/browser/dom_ui/shared_resources_data_source.cc b/chrome/browser/dom_ui/shared_resources_data_source.cc
index 709b33c2dee253d97bd5ea303c6a342a7268a91f..6170b68baef4ad0db2d0dded939abe68308fa6a2 100644
--- a/chrome/browser/dom_ui/shared_resources_data_source.cc
+++ b/chrome/browser/dom_ui/shared_resources_data_source.cc
@@ -32,6 +32,8 @@ int PathToIDR(const std::string& path) {
     idr = IDR_FOLDER_OPEN;
   } else if (path == "app/resources/folder_open_rtl.png") {
     idr = IDR_FOLDER_OPEN_RTL;
+  } else if (path == "app/resources/throbber.png") {
+    idr = IDR_THROBBER;
   } else {
     // The name of the files in the grd list are prefixed with the following
     // directory: