Add JSNative utility class with static methods methods to efficiently manipulate typed JSInterop ob…

pkg/compiler/lib/src/ssa/builder.dart

Index: pkg/compiler/lib/src/ssa/builder.dart
diff --git a/pkg/compiler/lib/src/ssa/builder.dart b/pkg/compiler/lib/src/ssa/builder.dart
index 9c7a31f397cb43a65a64743a02b3ab7e615f6aa0..71485817e97deae67a04c71db30ed7d9a49f1689 100644
--- a/pkg/compiler/lib/src/ssa/builder.dart
+++ b/pkg/compiler/lib/src/ssa/builder.dart
@@ -5619,14 +5619,15 @@ class SsaBuilder extends ast.Visitor
       var filteredArguments = <HInstruction>[];
       var parameterNameMap = new Map<String, js.Expression>();
       params.orderedForEachParameter((ParameterElement parameter) {
-        // TODO(jacobr): throw if parameter names do not match names of property
-        // names in the class.
+        // TODO(jacobr): consider throwing if parameter names do not match
+        // names of properties in the class.
         assert(parameter.isNamed);
         HInstruction argument = arguments[i];
         if (argument != null) {
           filteredArguments.add(argument);
-          parameterNameMap[parameter.name] =
-              new js.InterpolatedExpression(positions++);
+          var jsName =
+              backend.nativeData.getUnescapedJSInteropName(parameter.name);
+          parameterNameMap[jsName] = new js.InterpolatedExpression(positions++);
         }
         i++;
       });