Add RenderText DirectionalityMode enum and support; etc.

ui/views/controls/message_box_view.cc

Index: ui/views/controls/message_box_view.cc
diff --git a/ui/views/controls/message_box_view.cc b/ui/views/controls/message_box_view.cc
index 960b3161b8a09d0e1b4068725635a66df7fb099d..f3389f6f0ab15b4f38d1ec24fb77aaff8c49e318 100644
--- a/ui/views/controls/message_box_view.cc
+++ b/ui/views/controls/message_box_view.cc
@@ -11,6 +11,7 @@
 #include "ui/base/accessibility/accessible_view_state.h"
 #include "ui/base/clipboard/clipboard.h"
 #include "ui/base/clipboard/scoped_clipboard_writer.h"
+#include "ui/gfx/render_text.h"
 #include "ui/views/controls/button/checkbox.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
@@ -175,7 +176,7 @@ void MessageBoxView::Init(const InitParams& params) {
       // have a height of 0.
       message_label->SetMultiLine(!texts[i].empty());
       message_label->SetAllowCharacterBreak(true);
-      message_label->set_directionality_mode(Label::AUTO_DETECT_DIRECTIONALITY);
+      message_label->set_directionality_mode(gfx::DERIVE_FROM_TEXT);
       message_label->SetHorizontalAlignment(alignment);
       message_labels_.push_back(message_label);
     }