Revert of ipc: Change the timing of the construction of the attachment broker.

content/common/child_process_host_impl.cc

Index: content/common/child_process_host_impl.cc
diff --git a/content/common/child_process_host_impl.cc b/content/common/child_process_host_impl.cc
index 0c1fab2d4abb8433221ddc7b7d347ebae41233e7..071d96d207d0c424f5a0976a885a1dc3f96e7a4e 100644
--- a/content/common/child_process_host_impl.cc
+++ b/content/common/child_process_host_impl.cc
@@ -111,14 +111,6 @@
 #if defined(OS_WIN)
   AddFilter(new FontCacheDispatcher());
 #endif
-#if USE_ATTACHMENT_BROKER
-  // Ensure that the privileged attachment broker gets constructed 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.
-  GetAttachmentBroker();
-#endif
 }
 
 ChildProcessHostImpl::~ChildProcessHostImpl() {