Triage some co19 tests.

compiler/java/com/google/dart/compiler/resolver/Elements.java

Index: compiler/java/com/google/dart/compiler/resolver/Elements.java
diff --git a/compiler/java/com/google/dart/compiler/resolver/Elements.java b/compiler/java/com/google/dart/compiler/resolver/Elements.java
index e0474b5f8ae077da0d22a0e6aeec7ef766bd0f7b..a78636ced9842489c5c1b752dca9c470fdf5376d 100644
--- a/compiler/java/com/google/dart/compiler/resolver/Elements.java
+++ b/compiler/java/com/google/dart/compiler/resolver/Elements.java
@@ -934,4 +934,17 @@ static FieldElementImplementation fieldFromNode(DartField node,
     }
     return false;
   }
+  
+  public static boolean isFieldOfSameClassAsEnclosingConstructor(Element maybeField,
+      Element maybeConstructor) {
+    if (ElementKind.of(maybeField) == ElementKind.FIELD
+        && ElementKind.of(maybeConstructor) == ElementKind.CONSTRUCTOR) {
+      FieldElement field = (FieldElement) maybeField;
+      ConstructorElement constructor = (ConstructorElement) maybeConstructor;
+      if (field.getEnclosingElement() == constructor.getEnclosingElement()) {
+        return true;
+      }
+    }
+    return false;
+  }
 }