Change switch to give errors when cases don't follow the newest syntax.

tests/language/switch_test.dart

Index: tests/language/switch_test.dart
diff --git a/tests/language/switch_test.dart b/tests/language/switch_test.dart
index ec055dc6da4de478e67f68c0edc74b0dc3cd179d..a79a3e6f501ecde28a08691321e3eaa8f65baefd 100644
--- a/tests/language/switch_test.dart
+++ b/tests/language/switch_test.dart
@@ -46,6 +46,80 @@ class SwitchTest {
   }
 }
 
+
+class Enum {
+  static const Enum e1 = const Enum(1);
+  static const Enum e2 = const Enum(2);
+  static const Enum e3 = const Enum(3);
+  final int id;
+  const Enum(this.id);
+}
+
+void testSwitchEnum(Enum input, int expect) {
+  int result = null;
+  switch (input) {
+    case Enum.e1:
+      result = 10;
+      break;
+    case Enum.e2:
+      result = 20;
+      break;
+    case Enum.e3:
+      result = 30;
+      break;
+    default:
+      result = 40;
+  }
+  Expect.equals(expect, result);
+}
+
+const int ic1 = 1;
+const int ic2 = 2;
+void testSwitchIntExpression(int input, int expect) {
+  int result = null;
+  switch (input) {
+    case 1 + 1:  // 2
+    case ic1 + 2: // 3
+      result = 11;
+      break;
+    case ic2 * 2:  // 4
+    case 1 * 5:  // 5
+      result = 21;
+      break;
+    case ic1 % ic2 + 5:  // 6
+      result = 31;
+      break;
+  }
+  Expect.equals(expect, result);
+}
+
+void testSwitchBool(bool input, int expect) {
+  int result = null;
+  switch (input) {
+    case true:
+      result = 12;
+      break;
+    case false:
+      result = 22;
+  }
+  Expect.equals(expect, result);
+}
+
 main() {
   SwitchTest.testMain();
+
+  testSwitchEnum(Enum.e1, 10);
+  testSwitchEnum(Enum.e2, 20);
+  testSwitchEnum(Enum.e3, 30);
+  testSwitchEnum(null, 40);
+
+  testSwitchIntExpression(2, 11);
+  testSwitchIntExpression(3, 11);
+  testSwitchIntExpression(4, 21);
+  testSwitchIntExpression(5, 21);
+  testSwitchIntExpression(6, 31);
+  testSwitchIntExpression(7, null);
+
+  testSwitchBool(true, 12);
+  testSwitchBool(false, 22);
 }