Don't allow whitespace after sign characters in parseInt.

src/conversions.cc

Index: src/conversions.cc
diff --git a/src/conversions.cc b/src/conversions.cc
index 14585845de2f55c47d2052402cef3bcc1531650e..5cf5efd2789d55b18a3d216e830c8ccf17761ce3 100644
--- a/src/conversions.cc
+++ b/src/conversions.cc
@@ -254,12 +254,12 @@ static double InternalStringToInt(UnicodeCache* unicode_cache,
   if (*current == '+') {
     // Ignore leading sign; skip following spaces.
     ++current;
-    if (!AdvanceToNonspace(unicode_cache, &current, end)) {
+    if (current == end) {
       return JUNK_STRING_VALUE;
     }
   } else if (*current == '-') {
     ++current;
-    if (!AdvanceToNonspace(unicode_cache, &current, end)) {
+    if (current == end) {
       return JUNK_STRING_VALUE;
     }
     negative = true;