Refactor ViewsDelegate and MD-ify the icon-to-text spacing for checkbox and radiobutton

ui/views/examples/dialog_example.cc

Index: ui/views/examples/dialog_example.cc
diff --git a/ui/views/examples/dialog_example.cc b/ui/views/examples/dialog_example.cc
index 637c6dafabb1957002431d3e709998ed9e4c4af4..7c80d378a9a81296eaf440a7f620572369c755b8 100644
--- a/ui/views/examples/dialog_example.cc
+++ b/ui/views/examples/dialog_example.cc
@@ -131,8 +131,8 @@ void DialogExample::CreateExampleView(View* container) {
   const float kFixed = 0.f;
   const float kStretchy = 1.f;
 
-  const int horizontal_spacing =
-      ViewsDelegate::GetInstance()->GetDialogRelatedButtonHorizontalSpacing();
+  const int horizontal_spacing = ViewsDelegate::GetInstance()->GetSpacingMetric(
+      views::SpacingMetric::RELATED_HORIZONTAL_BUTTON);
   GridLayout* layout = GridLayout::CreatePanel(container);
   container->SetLayoutManager(layout);
   ColumnSet* column_set = layout->AddColumnSet(kFieldsColumnId);
@@ -187,7 +187,8 @@ void DialogExample::StartRowWithLabel(GridLayout* layout, const char* label) {
   const float kFixedVerticalResize = 0.f;
   layout->StartRowWithPadding(
       kFixedVerticalResize, kFieldsColumnId, kFixedVerticalResize,
-      ViewsDelegate::GetInstance()->GetDialogRelatedControlVerticalSpacing());
+      ViewsDelegate::GetInstance()->GetSpacingMetric(
+          views::SpacingMetric::RELATED_VERTICAL_CONTROL));
   layout->AddView(new Label(base::ASCIIToUTF16(label)));
 }