Make test of malformed types a dynamic type error.

sdk/lib/_internal/compiler/implementation/ssa/optimize.dart

Index: sdk/lib/_internal/compiler/implementation/ssa/optimize.dart
diff --git a/sdk/lib/_internal/compiler/implementation/ssa/optimize.dart b/sdk/lib/_internal/compiler/implementation/ssa/optimize.dart
index 6b83cda776b8c356337cd743c3baa964dedede71..d947b91e37b65186375006bf96ad2f65c23e9ff2 100644
--- a/sdk/lib/_internal/compiler/implementation/ssa/optimize.dart
+++ b/sdk/lib/_internal/compiler/implementation/ssa/optimize.dart
@@ -594,6 +594,11 @@ class SsaInstructionSimplifier extends HBaseVisitor
     HInstruction value = node.inputs[0];
     DartType type = node.typeExpression;
     if (type != null) {
+      if (type.kind == TypeKind.MALFORMED_TYPE) {
+        // Malformed types are treated as dynamic statically, but should
+        // throw a type error at runtime.
+        return node;
+      }
       if (!type.treatAsRaw || type.kind == TypeKind.TYPE_VARIABLE) {
         return node;
       }