[ash-md] Fixed TriView to relayout child Views when their preferred size changed.

ui/views/test/test_views.cc

Index: ui/views/test/test_views.cc
diff --git a/ui/views/test/test_views.cc b/ui/views/test/test_views.cc
index 837f2cece5a0d0abb51597bf3406cda83720ac8c..6755dba1e0436d7248477afb5c9b1451d7bf590b 100644
--- a/ui/views/test/test_views.cc
+++ b/ui/views/test/test_views.cc
@@ -35,6 +35,11 @@ ProportionallySizedView::ProportionallySizedView(int factor)
 
 ProportionallySizedView::~ProportionallySizedView() {}
 
+void ProportionallySizedView::SetPreferredWidth(int width) {
+  preferred_width_ = width;
+  PreferredSizeChanged();
+}
+
 int ProportionallySizedView::GetHeightForWidth(int w) const {
   return w * factor_;
 }