Add a proper HInvokeConstructorBody instead of mis-using HInvokeDynamicMethod.

sdk/lib/_internal/compiler/implementation/ssa/tracer.dart

Index: sdk/lib/_internal/compiler/implementation/ssa/tracer.dart
===================================================================
--- sdk/lib/_internal/compiler/implementation/ssa/tracer.dart	(revision 23010)
+++ sdk/lib/_internal/compiler/implementation/ssa/tracer.dart	(working copy)
@@ -355,9 +355,7 @@
 
   String visitInvokeStatic(HInvokeStatic invoke) {
     String target = invoke.element.name.slowToString();
-    int offset = HInvoke.ARGUMENTS_OFFSET;
-    List arguments = invoke.inputs.sublist(offset);
-    return visitGenericInvoke("Invoke", target, arguments);
+    return visitGenericInvoke("Invoke", target, invoke.inputs);
   }
 
   String visitInvokeSuper(HInvokeSuper invoke) {
@@ -367,6 +365,13 @@
     return visitGenericInvoke("Invoke super", target, arguments);
   }
 
+  String visitInvokeConstructorBody(HInvokeConstructorBody invoke) {
+    String target = invoke.element.name.slowToString();
+    int offset = HInvoke.ARGUMENTS_OFFSET + 1;
+    List arguments = invoke.inputs.sublist(offset);
+    return visitGenericInvoke("Invoke constructor body", target, arguments);
+  }
+
   String visitForeign(HForeign foreign) {
     return visitGenericInvoke("Foreign", "${foreign.codeAst}", foreign.inputs);
   }