[regexp] clear QuickCheckDetails for backward reads.

src/regexp/jsregexp.h

Index: src/regexp/jsregexp.h
diff --git a/src/regexp/jsregexp.h b/src/regexp/jsregexp.h
index 3ce9f131110fd80bb904f38b02150dbf65ec7384..8bc814f40ff29489a439c426ee780f3bb7ebe4e1 100644
--- a/src/regexp/jsregexp.h
+++ b/src/regexp/jsregexp.h
@@ -1114,11 +1114,11 @@ class ChoiceNode: public RegExpNode {
 };
 
 
-class NegativeLookaheadChoiceNode: public ChoiceNode {
+class NegativeLookaroundChoiceNode : public ChoiceNode {
  public:
-  explicit NegativeLookaheadChoiceNode(GuardedAlternative this_must_fail,
-                                       GuardedAlternative then_do_this,
-                                       Zone* zone)
+  explicit NegativeLookaroundChoiceNode(GuardedAlternative this_must_fail,
+                                        GuardedAlternative then_do_this,
+                                        Zone* zone)
       : ChoiceNode(2, zone) {
     AddAlternative(this_must_fail);
     AddAlternative(then_do_this);