ipc: Move AttachmentBrokerPrivileged singleton logic into ipc/.

content/browser/browser_child_process_host_impl.cc

Index: content/browser/browser_child_process_host_impl.cc
diff --git a/content/browser/browser_child_process_host_impl.cc b/content/browser/browser_child_process_host_impl.cc
index 2f9076f0fa4a05487c2fa5c29817c5e6ebb78668..9a4ab0b2facafddf49cd2bdf0c319ee38c88fbef 100644
--- a/content/browser/browser_child_process_host_impl.cc
+++ b/content/browser/browser_child_process_host_impl.cc
@@ -30,6 +30,8 @@
 #include "content/public/common/content_switches.h"
 #include "content/public/common/process_type.h"
 #include "content/public/common/result_codes.h"
+#include "ipc/attachment_broker.h"
+#include "ipc/attachment_broker_privileged.h"
 
 #if defined(OS_MACOSX)
 #include "content/browser/mach_broker_mac.h"
@@ -117,6 +119,19 @@ BrowserChildProcessHostImpl::BrowserChildProcessHostImpl(
       power_monitor_message_broadcaster_(this) {
   data_.id = ChildProcessHostImpl::GenerateChildProcessUniqueId();
 
+#if USE_ATTACHMENT_BROKER
+  // Construct the privileged attachment broker early in the life cycle of a
+  // child process. This ensures that when a test is being run in one of the
+  // single process modes, the global attachment broker is the privileged
+  // attachment broker, rather than an unprivileged attachment broker.
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+  IPC::AttachmentBrokerPrivileged::CreateBrokerIfNeeded(
+      MachBroker::GetInstance());
+#else
+  IPC::AttachmentBrokerPrivileged::CreateBrokerIfNeeded();
+#endif  // defined(OS_MACOSX) && !defined(OS_IOS)
+#endif  // USE_ATTACHMENT_BROKER
+
   child_process_host_.reset(ChildProcessHost::Create(this));
   AddFilter(new TraceMessageFilter(data_.id));
   AddFilter(new ProfilerMessageFilter(process_type));