Enabled pressing TAB to cycle through the Omnibox results.

chrome/browser/ui/views/omnibox/omnibox_view_views.cc

Index: chrome/browser/ui/views/omnibox/omnibox_view_views.cc
===================================================================
--- chrome/browser/ui/views/omnibox/omnibox_view_views.cc	(revision 117356)
+++ chrome/browser/ui/views/omnibox/omnibox_view_views.cc	(working copy)
@@ -239,10 +239,18 @@
     handled = true;
   } else if (!handled &&
              event.key_code() == ui::VKEY_TAB &&
-             !event.IsShiftDown() &&
              !event.IsControlDown()) {
-    if (model_->is_keyword_hint()) {
+    if (model_->is_keyword_hint() && !event.IsShiftDown()) {
       handled = model_->AcceptKeyword();
+    } else if (model_->popup_model()->IsOpen()) {
+      if (event.IsShiftDown() &&
+          model_->popup_model()->selected_line_state() ==
+              AutocompletePopupModel::KEYWORD) {
+        model_->ClearKeyword(GetText());
+      } else {
+        model_->OnUpOrDownKeyPressed(event.IsShiftDown() ? -1 : 1);
+      }
+      handled = true;
     } else {
       string16::size_type start = 0;
       string16::size_type end = 0;