Fix bug in cache handling of lastIndex on global regexps.

src/regexp.js

Index: src/regexp.js
diff --git a/src/regexp.js b/src/regexp.js
index faa525d62da27ca518e3b4fa8ec12f6ab2cbdaa8..59c40407fbc20ddc4406d0ef2661d7d9bcf39099 100644
--- a/src/regexp.js
+++ b/src/regexp.js
@@ -186,10 +186,10 @@ function RegExpExec(string) {
       %_IsRegExpEquivalent(cache.regExp, this) &&
       %_ObjectEquals(cache.subject, string)) {
     if (cache.answerSaved) {
-      // If this regexp is not global, cache.lastIndex is zero, so we only get 
+      // If this regexp is global, cache.lastIndex is zero, so we only get
       // here if this.lastIndex is zero, and resulting this.lastIndex
       // must be zero too, so no change is necessary.
-      if (this.global) this.lastIndex = lastMatchInfo[CAPTURE1];
+      if (!this.global) this.lastIndex = lastMatchInfo[CAPTURE1];
       return %_RegExpCloneResult(cache.answer);
     } else {
       saveAnswer = true;