Make sure we short-circuit the second corruption test, it might be crashing firefox

tools/dom/src/Validators.dart

Index: tools/dom/src/Validators.dart
diff --git a/tools/dom/src/Validators.dart b/tools/dom/src/Validators.dart
index d964153afea1d46ce71e489f3bd4773977f9dc05..4dbe32c5942269275d38bf590e5d6a5cf60e1c0f 100644
--- a/tools/dom/src/Validators.dart
+++ b/tools/dom/src/Validators.dart
@@ -214,8 +214,7 @@ class _ValidatingTreeSanitizer implements NodeTreeSanitizer {
       // On IE, erratically, the hasCorruptedAttributes test can return false,
       // even though it clearly is corrupted. A separate copy of the test
       // inlining just the basic check seems to help.
-      var corruptedTest2 = Element._hasCorruptedAttributesAdditionalCheck(element);
-      corrupted = corruptedTest1 || corruptedTest2;
+      corrupted = corruptedTest1 ? true : Element._hasCorruptedAttributesAdditionalCheck(element);
     } catch(e) {}
     var elementText = 'element unprintable';
     try {