Add Isolate::DiscardThreadSpecificMetadata method to embedder API.

src/isolate.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/isolate.h"
 
 #include <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
@@ skipping 117 matching lines @@
     if (per_thread == NULL) {
       per_thread = new PerIsolateThreadData(this, thread_id);
       thread_data_table_->Insert(per_thread);
     }
     DCHECK(thread_data_table_->Lookup(this, thread_id) == per_thread);
   }
   return per_thread;
 }
 
 
+void Isolate::DiscardPerThreadDataForThisThread() {
+  int thread_id_int = base::Thread::GetThreadLocalInt(Isolate::thread_id_key_);
+  if (thread_id_int) {
+    ThreadId thread_id = ThreadId(thread_id_int);
+    DCHECK(!thread_manager_->mutex_owner_.Equals(thread_id));
+    base::LockGuard<base::Mutex> lock_guard(thread_data_table_mutex_.Pointer());
+    PerIsolateThreadData* per_thread =
+        thread_data_table_->Lookup(this, thread_id);
+    if (per_thread) {
+      DCHECK(!per_thread->thread_state_);
+      thread_data_table_->Remove(per_thread);
+    }
+  }
+}
+
+
 Isolate::PerIsolateThreadData* Isolate::FindPerThreadDataForThisThread() {
   ThreadId thread_id = ThreadId::Current();
   return FindPerThreadDataForThread(thread_id);
 }
 
 
 Isolate::PerIsolateThreadData* Isolate::FindPerThreadDataForThread(
     ThreadId thread_id) {
   PerIsolateThreadData* per_thread = NULL;
   {
@@ skipping 2661 matching lines @@
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8