ui: Clean up naming of paint-related identifiers

ui/views/controls/button/radio_button.cc

Index: ui/views/controls/button/radio_button.cc
diff --git a/ui/views/controls/button/radio_button.cc b/ui/views/controls/button/radio_button.cc
index 0a2c89c830d067e387004ce7b1cb5c7d345c9284..ca859890df3b4d0238cfb405222fe849185272e0 100644
--- a/ui/views/controls/button/radio_button.cc
+++ b/ui/views/controls/button/radio_button.cc
@@ -148,9 +148,9 @@ void RadioButton::SetChecked(bool checked) {
 }
 
 void RadioButton::PaintFocusRing(gfx::Canvas* canvas,
-                                 const cc::PaintFlags& paint) {
+                                 const cc::PaintFlags& flags) {
   canvas->DrawCircle(gfx::RectF(image()->bounds()).CenterPoint(),
-                     image()->width() / 2, paint);
+                     image()->width() / 2, flags);
 }
 
 const gfx::VectorIcon& RadioButton::GetVectorIcon() const {