Added labelled thread names to help with some debugging activity. Right now,...

src/top.cc

Index: src/top.cc
===================================================================
--- src/top.cc	(revision 6114)
+++ src/top.cc	(working copy)
@@ -170,7 +170,12 @@
 // into for use by a stacks only core dump (aka minidump).
 class PreallocatedMemoryThread: public Thread {
  public:
-  PreallocatedMemoryThread() : keep_running_(true) {
+  PreallocatedMemoryThread()
+    :
+#ifdef DEBUG_THREAD_NAMES
+      Thread("v8:PreallocMem"),
+#endif
+      keep_running_(true) {
     wait_for_ever_semaphore_ = OS::CreateSemaphore(0);
     data_ready_semaphore_ = OS::CreateSemaphore(0);
   }