Port regexp fix (backslash-b at end of input) to

src/jsregexp.cc

Index: src/jsregexp.cc
===================================================================
--- src/jsregexp.cc	(revision 4511)
+++ src/jsregexp.cc	(working copy)
@@ -4870,17 +4870,18 @@
 
     SetRelation word_relation =
         CharacterRange::WordCharacterRelation(following_chars);
-    if (word_relation.ContainedIn()) {
-      // Following character is definitely a word character.
+    if (word_relation.Disjoint()) {
+      // Includes the case where following_chars is empty (e.g., end-of-input).
+      // Following character is definitely *not* a word character.
       type = (type == AssertionNode::AT_BOUNDARY) ?
-                  AssertionNode::AFTER_NONWORD_CHARACTER :
-                  AssertionNode::AFTER_WORD_CHARACTER;
+                 AssertionNode::AFTER_WORD_CHARACTER :
+                 AssertionNode::AFTER_NONWORD_CHARACTER;
       that->set_type(type);
-    } else if (word_relation.Disjoint()) {
-      // Following character is definitely *not* a word character.
+    } else if (word_relation.ContainedIn()) {
+      // Following character is definitely a word character.
       type = (type == AssertionNode::AT_BOUNDARY) ?
-                  AssertionNode::AFTER_WORD_CHARACTER :
-                  AssertionNode::AFTER_NONWORD_CHARACTER;
+                 AssertionNode::AFTER_NONWORD_CHARACTER :
+                 AssertionNode::AFTER_WORD_CHARACTER;
       that->set_type(type);
     }
   }