fix for static methods and names banned in strict mode

test/codegen/expect/DeltaBlue.js

 var DeltaBlue;
 (function(exports) {
   'use strict';
   // Function main: () → dynamic
   function main() {
     new DeltaBlue().report();
   }
   class DeltaBlue extends BenchmarkBase.BenchmarkBase {
     DeltaBlue() {
       super.BenchmarkBase("DeltaBlue");
@@ skipping 11 matching lines @@
     nextWeaker() {
       return /* Unimplemented const */new List.from([STRONG_PREFERRED, PREFERRED, STRONG_DEFAULT, NORMAL, WEAK_DEFAULT, WEAKEST]).get(this.value);
     }
     static stronger(s1, s2) {
       return dart.notNull(s1.value) < dart.notNull(s2.value);
     }
     static weaker(s1, s2) {
       return dart.notNull(s1.value) > dart.notNull(s2.value);
     }
     static weakest(s1, s2) {
-      return weaker(s1, s2) ? s1 : s2;
+      return Strength.weaker(s1, s2) ? s1 : s2;
     }
     static strongest(s1, s2) {
-      return stronger(s1, s2) ? s1 : s2;
+      return Strength.stronger(s1, s2) ? s1 : s2;
     }
   }
   let REQUIRED = new Strength(0, "required");
   let STRONG_PREFERRED = new Strength(1, "strongPreferred");
   let PREFERRED = new Strength(2, "preferred");
   let STRONG_DEFAULT = new Strength(3, "strongDefault");
   let NORMAL = new Strength(4, "normal");
   let WEAK_DEFAULT = new Strength(5, "weakDefault");
   let WEAKEST = new Strength(6, "weakest");
   class Constraint extends core.Object {
@@ skipping 414 matching lines @@
   exports.BinaryConstraint = BinaryConstraint;
   exports.ScaleConstraint = ScaleConstraint;
   exports.EqualityConstraint = EqualityConstraint;
   exports.Variable = Variable;
   exports.Planner = Planner;
   exports.Plan = Plan;
   exports.chainTest = chainTest;
   exports.projectionTest = projectionTest;
   exports.change = change;
 })(DeltaBlue || (DeltaBlue = {}));