Fixed a known issue in D8 (read file), enabled D8 shared library build on Windows.

src/v8threads.cc

 // Copyright 2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 76 matching lines @@
 
 bool Locker::IsLocked(v8::Isolate* isolate) {
   i::Isolate* internal_isolate = reinterpret_cast<i::Isolate*>(isolate);
   if (internal_isolate == NULL) {
     internal_isolate = i::Isolate::GetDefaultIsolateForLocking();
   }
   return internal_isolate->thread_manager()->IsLockedByCurrentThread();
 }
 
 
+bool Locker::IsActive() {
+  return active_;
+}
+
+
 Locker::~Locker() {
   ASSERT(isolate_->thread_manager()->IsLockedByCurrentThread());
   if (has_lock_) {
     if (isolate_->IsDefaultIsolate()) {
       isolate_->Exit();
     }
     if (top_level_) {
       isolate_->thread_manager()->FreeThreadResources();
     } else {
       isolate_->thread_manager()->ArchiveThread();
@@ skipping 349 matching lines @@
 // Acknowledge the preemption by the receiving thread.
 void ContextSwitcher::PreemptionReceived() {
   ASSERT(Locker::IsLocked());
   // There is currently no accounting being done for this. But could be in the
   // future, which is why we leave this in.
 }
 
 
 }  // namespace internal
 }  // namespace v8