Force inlining for _ElementCssClassSet.add() / .remove()

tools/dom/src/dart2js_CssClassSet.dart

Index: tools/dom/src/dart2js_CssClassSet.dart
diff --git a/tools/dom/src/dart2js_CssClassSet.dart b/tools/dom/src/dart2js_CssClassSet.dart
index 087685f95ba5b23cbf00d9efc14d5a50d80eb190..758419d755098aab2c12d4280552a9c21f2f070b 100644
--- a/tools/dom/src/dart2js_CssClassSet.dart
+++ b/tools/dom/src/dart2js_CssClassSet.dart
@@ -140,6 +140,7 @@ class _ElementCssClassSet extends CssClassSetImpl {
     return value is String && _classListContains(_classListOf(_element), value);
   }
 
+  @ForceInline()
   static bool _add(Element _element, String value) {
     DomTokenList list = _classListOf(_element);
     // Compute returned result independently of action upon the set.
@@ -148,6 +149,7 @@ class _ElementCssClassSet extends CssClassSetImpl {
     return added;
   }
 
+  @ForceInline()
   static bool _remove(Element _element, String value) {
     DomTokenList list = _classListOf(_element);
     bool removed = _classListContainsBeforeAddOrRemove(list, value);