Push version 1.3.4 to trunk....

src/v8.cc

Index: src/v8.cc
===================================================================
--- src/v8.cc	(revision 2677)
+++ src/v8.cc	(working copy)
@@ -156,7 +156,16 @@
   return (hi << 16) + (lo & 0xFFFF);
 }
 
+void V8::IdleNotification(bool is_high_priority) {
+  if (!FLAG_use_idle_notification) return;
+  // Ignore high priority instances of V8.
+  if (is_high_priority) return;
 
+  // Uncommit unused memory in new space.
+  Heap::UncommitFromSpace();
+}
+
+
 Smi* V8::RandomPositiveSmi() {
   uint32_t random = Random();
   ASSERT(IsPowerOf2(Smi::kMaxValue + 1));