Fix lingering switch statement test failures.

pkg/compiler/lib/src/resolution/members.dart

Index: pkg/compiler/lib/src/resolution/members.dart
diff --git a/pkg/compiler/lib/src/resolution/members.dart b/pkg/compiler/lib/src/resolution/members.dart
index 8644d31efde6798b5217772ab86f9c0d38f47a29..e2c8b91da449e3b8953ac6a33b0a3af9de9c4fbe 100644
--- a/pkg/compiler/lib/src/resolution/members.dart
+++ b/pkg/compiler/lib/src/resolution/members.dart
@@ -4601,6 +4601,7 @@ class ResolverVisitor extends MappingVisitor<ResolutionResult> {
 
     JumpTarget breakElement = getOrDefineTarget(node);
     Map<String, LabelDefinition> continueLabels = <String, LabelDefinition>{};
+    Set<SwitchCase> switchCasesWithContinues = new Set<SwitchCase>();
     Link<Node> cases = node.cases.nodes;
     while (!cases.isEmpty) {
       SwitchCase switchCase = cases.head;
@@ -4668,12 +4669,22 @@ class ResolverVisitor extends MappingVisitor<ResolutionResult> {
     node.cases.accept(this);
     statementScope.exitSwitch();
 
+    continueLabels.forEach((String key, LabelDefinition label) {
+      if (label.isContinueTarget) {
+        JumpTarget targetElement = label.target;
+        SwitchCase switchCase = targetElement.statement;
+        switchCasesWithContinues.add(switchCase);
+      }
+    });
+
     // Clean-up unused labels.
     continueLabels.forEach((String key, LabelDefinition label) {
       if (!label.isContinueTarget) {
         JumpTarget targetElement = label.target;
         SwitchCase switchCase = targetElement.statement;
-        registry.undefineTarget(switchCase);
+        if (!switchCasesWithContinues.contains(switchCase)) {
+          registry.undefineTarget(switchCase);
+        }
         registry.undefineLabel(label.label);
       }
     });