Correctly initialize regexp global cache.

src/jsregexp.cc

Index: src/jsregexp.cc
diff --git a/src/jsregexp.cc b/src/jsregexp.cc
index ae25432a587d19b9adb1c0d9f9bdc206ed161bda..e59170d5a315caa6feda341b6d6bb28103e152fe 100644
--- a/src/jsregexp.cc
+++ b/src/jsregexp.cc
@@ -706,16 +706,17 @@ Handle<JSArray> RegExpImpl::SetLastMatchInfo(Handle<JSArray> last_match_info,
 RegExpImpl::GlobalCache::GlobalCache(Handle<JSRegExp> regexp,
                                      Handle<String> subject,
                                      bool is_global,
-                                     Isolate* isolate) {
+                                     Isolate* isolate)
+  : register_array_(NULL),
+    register_array_size_(0),
+    regexp_(regexp),
+    subject_(subject) {
 #ifdef V8_INTERPRETED_REGEXP
   bool interpreted = true;
 #else
   bool interpreted = false;
 #endif  // V8_INTERPRETED_REGEXP
 
-  regexp_ = regexp;
-  subject_ = subject;
-
   if (regexp_->TypeTag() == JSRegExp::ATOM) {
     static const int kAtomRegistersPerMatch = 2;
     registers_per_match_ = kAtomRegistersPerMatch;