RegExp: Fix update of lastIndex on non-global sticky

R=yangguo@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1378693004

Cr-Commit-Position: refs/heads/master@{#31133}

src/regexp.js

@@ -143,6 +143,10 @@ function RegExpExecNoTests(regexp, string, start) {
   var matchInfo = %_RegExpExec(regexp, string, start, RegExpLastMatchInfo);
   if (matchInfo !== null) {
     $regexpLastMatchInfoOverride = null;
+    // ES6 21.2.5.2.2 step 18.
+    if (FLAG_harmony_regexps && regexp.sticky) {
+      regexp.lastIndex = matchInfo[CAPTURE1];
+    }
     RETURN_NEW_RESULT_FROM_MATCH_INFO(matchInfo, string);
   }
   regexp.lastIndex = 0;

test/mjsunit/harmony/regexp-sticky.js

@@ -40,13 +40,13 @@ assertTrue(!!"..foobar".match(plain));
 var sticky = /foo.bar/y;
 
 assertTrue(!!"foo*bar".match(sticky));
-assertEquals(0, sticky.lastIndex);
+assertEquals(7, sticky.lastIndex);
 assertFalse(!!"..foo*bar".match(sticky));
 
 var stickyplain = /foobar/y;
 
 assertTrue(!!"foobar".match(stickyplain));
-assertEquals(0, stickyplain.lastIndex);
+assertEquals(6, stickyplain.lastIndex);
 assertFalse(!!"..foobar".match(stickyplain));
 
 var global = /foo.bar/g;