Add a sandbox API for broker handle duplication

sandbox/src/broker_services.cc

Index: sandbox/src/broker_services.cc
===================================================================
--- sandbox/src/broker_services.cc	(revision 129865)
+++ sandbox/src/broker_services.cc	(working copy)
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -184,6 +184,10 @@
 
         case JOB_OBJECT_MSG_EXIT_PROCESS:
         case JOB_OBJECT_MSG_ABNORMAL_EXIT_PROCESS: {
+          {
+            AutoLock lock(&broker->lock_);
+            broker->child_process_ids_.erase(reinterpret_cast<DWORD>(ovl));
+          }
           --target_counter;
           if (0 == target_counter)
             ::SetEvent(no_targets);
@@ -292,6 +296,7 @@
   // Save the tracker because in cleanup we might need to force closing
   // the Jobs.
   tracker_list_.push_back(tracker);
+  child_process_ids_.insert(process_info.dwProcessId);
 
   // We return the caller a duplicate of the process handle so they
   // can close it at will.
@@ -312,4 +317,9 @@
   return SBOX_ALL_OK;
 }
 
+bool BrokerServicesBase::IsActiveTarget(DWORD process_id) {
+  AutoLock lock(&lock_);
+  return child_process_ids_.find(process_id) != child_process_ids_.end();
+}
+
 }  // namespace sandbox