Remove Comprehension type in polymer expressions

pkg/polymer_expressions/test/eval_test.dart

Index: pkg/polymer_expressions/test/eval_test.dart
diff --git a/pkg/polymer_expressions/test/eval_test.dart b/pkg/polymer_expressions/test/eval_test.dart
index 2181215eb887734966d55aa0c17e4ef764e5d916..8ca3490946315ca92037400ec828c3479a49722a 100644
--- a/pkg/polymer_expressions/test/eval_test.dart
+++ b/pkg/polymer_expressions/test/eval_test.dart
@@ -218,22 +218,33 @@ main() {
 
     test('should evaluate an "in" expression', () {
       var scope = new Scope(variables: {'items': [1, 2, 3]});
-      var comprehension = eval(parse('item in items'), scope);
-      expect(comprehension.iterable, orderedEquals([1, 2, 3]));
+      var childScopes = eval(parse('item in items'), scope);
+      expect(childScopes.length, 3);
+      expect(childScopes[0].varName, 'item');
+      expect(childScopes[0].value, 1);
+      expect(childScopes[1].varName, 'item');
+      expect(childScopes[1].value, 2);
+      expect(childScopes[2].varName, 'item');
+      expect(childScopes[2].value, 3);
     });
 
     test('should evaluate complex "in" expressions', () {
       var holder = new ListHolder([1, 2, 3]);
       var scope = new Scope(variables: {'holder': holder});
-      var comprehension = eval(parse('item in holder.items'), scope);
-      expect(comprehension.iterable, orderedEquals([1, 2, 3]));
+      var childScopes = eval(parse('item in holder.items'), scope);
+      expect(childScopes.length, 3);
+      expect(childScopes[0].varName, 'item');
+      expect(childScopes[0].value, 1);
+      expect(childScopes[1].varName, 'item');
+      expect(childScopes[1].value, 2);
+      expect(childScopes[2].varName, 'item');
+      expect(childScopes[2].value, 3);
     });
 
     test('should handle null iterators in "in" expressions', () {
       var scope = new Scope(variables: {'items': null});
-      var comprehension = eval(parse('item in items'), scope);
-      expect(comprehension, isNotNull);
-      expect(comprehension.iterable, []);
+      var childScopes = eval(parse('item in items'), scope);
+      expect(childScopes.length, 0);
     });
 
   });
@@ -345,11 +356,12 @@ main() {
       var foo = new Foo(name: 'foo');
       return expectObserve('item in items',
           variables: {'items': items},
-          beforeMatcher: (c) => c.iterable.isEmpty,
+          beforeMatcher: (c) => c.isEmpty,
           mutate: () {
             items.add(foo);
           },
-          afterMatcher: (c) => c.iterable.contains(foo)
+          afterMatcher:
+              (c) => c.single.varName == 'item' && c.single.value == foo
       );
     });