RegExp: Add support for the ES6-proposed sticky flag

src/jsregexp.h

Index: src/jsregexp.h
diff --git a/src/jsregexp.h b/src/jsregexp.h
index 1a97a30e5a47925eb51e95f1cf90c0903324a817..c65adea4c5cf04d6e92f02642b4eb7ee44fa36df 100644
--- a/src/jsregexp.h
+++ b/src/jsregexp.h
@@ -1661,7 +1661,7 @@ class RegExpEngine: public AllStatic {
   };
 
   static CompilationResult Compile(RegExpCompileData* input, bool ignore_case,
-                                   bool global, bool multiline,
+                                   bool global, bool multiline, bool sticky,
                                    Handle<String> pattern,
                                    Handle<String> sample_subject,
                                    bool is_one_byte, Zone* zone);