Implement date library functions in C++.

src/isolate.cc

Index: src/isolate.cc
diff --git a/src/isolate.cc b/src/isolate.cc
index 93742bd7cde1e77e5ff83b13d836b72b7f645a6d..3dfcbb5a3fd814645eac62573de595e9b9246213 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -1486,6 +1486,7 @@ Isolate::Isolate()
       has_installed_extensions_(false),
       string_tracker_(NULL),
       regexp_stack_(NULL),
+      date_cache_(NULL),
       embedder_data_(NULL),
       context_exit_happened_(false) {
   TRACE_ISOLATE(constructor);
@@ -1618,6 +1619,9 @@ Isolate::~Isolate() {
   delete unicode_cache_;
   unicode_cache_ = NULL;
 
+  delete date_cache_;
+  date_cache_ = NULL;
+
   delete regexp_stack_;
   regexp_stack_ = NULL;
 
@@ -1782,6 +1786,7 @@ bool Isolate::Init(Deserializer* des) {
   stub_cache_ = new StubCache(this);
   regexp_stack_ = new RegExpStack();
   regexp_stack_->isolate_ = this;
+  date_cache_ = new DateCache();
 
   // Enable logging before setting up the heap
   logger_->SetUp();