Issue 1105: Duplicate initialization should have a compile error

compiler/javatests/com/google/dart/compiler/resolver/NegativeResolverTest.java

Index: compiler/javatests/com/google/dart/compiler/resolver/NegativeResolverTest.java
diff --git a/compiler/javatests/com/google/dart/compiler/resolver/NegativeResolverTest.java b/compiler/javatests/com/google/dart/compiler/resolver/NegativeResolverTest.java
index 85e5240710eb20d89e07fe1e1cdee5269e845a02..f98483b1baf2fd04e0a0df174941fa19817f31bb 100644
--- a/compiler/javatests/com/google/dart/compiler/resolver/NegativeResolverTest.java
+++ b/compiler/javatests/com/google/dart/compiler/resolver/NegativeResolverTest.java
@@ -1074,4 +1074,16 @@ public class NegativeResolverTest extends CompilerTestCase {
         "class MyClass implements Map<Object, Dynamic> {",
         "}"));
   }
+
+  public void testConstructorDuplicateInitializationTest() {
+    checkSourceErrors(
+        makeCode(
+            "class A {",
+            "  A.one(this.x) : this.x = 42;",
+            "  A.two(y) : this.x = y, x = y;",
+            "  var x;",
+            "}"),
+        errEx(ResolverErrorCode.DUPLICATE_INITIALIZATION, 2, 19, 11),
+        errEx(ResolverErrorCode.DUPLICATE_INITIALIZATION, 3, 26, 5));
+  }
 }