Use Mojo pipes to signal sync IPC events

components/nacl/loader/BUILD.gn

 # Copyright 2015 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.
 
 import("//build/config/features.gni")
 import("//build/config/nacl/config.gni")
 import("//testing/test.gni")
 
 assert(enable_nacl)
 
@@ skipping 15 matching lines @@
     "nacl_validation_query.cc",
     "nacl_validation_query.h",
   ]
 
   deps = [
     ":minimal_content_dummy",
     "//base",
     "//components/nacl/common:minimal",
     "//crypto",
     "//ipc",
+    "//mojo/edk/system",
     "//native_client/src/trusted/service_runtime:sel_main_chrome",
     "//ppapi/c",
     "//ppapi/proxy:ipc",
     "//sandbox",
   ]
 }
 
 # This exists just to make 'gn check' happy with :minimal and
 # :nacl_helper_win_64 (below).  They can't depend on //content/public/common
 # or anything like that, because that would bring in lots more than counts
@@ skipping 63 matching lines @@
 
     deps = [
       ":loader",
       "//base",
       "//build/config/sanitizers:deps_no_options",
       "//components/nacl/common:switches",
       "//components/nacl/loader/sandbox_linux",
       "//content/public/common",
       "//crypto",
       "//ipc",
+      "//mojo/edk/system",
       "//sandbox/linux:sandbox_services",
       "//url/ipc:url_ipc",
     ]
 
     cflags = [ "-fPIE" ]
 
     ldflags = [ "-pie" ]
 
     data_deps = [
       "//native_client/src/trusted/service_runtime/linux:bootstrap",
@@ skipping 70 matching lines @@
       "nonsfi/nonsfi_main.cc",
       "nonsfi/nonsfi_main.h",
     ]
     deps = [
       ":nacl_helper_nonsfi_sandbox",
       "//base",
       "//components/nacl/common:switches",
       "//components/tracing",
       "//content",
       "//ipc",
+      "//mojo/edk/system",
       "//native_client/src/nonsfi/irt:nacl_sys_private",
       "//native_client/src/nonsfi/loader:elf_loader",
 
       # Normally libnacl is included implicitly by libc and is part of the
       # toolchain. But //build/config/nacl:compiler uses -nodefaultlibs and so
       # omits the default libnacl. When the nonsfi toolchain is more complete
       # and that kludge is no longer required, this dependency should be
       # removed.
       "//native_client/src/untrusted/nacl",
       "//ppapi/proxy",
@@ skipping 56 matching lines @@
       "${root_out_dir}/nacl_helper_nonsfi_unittests_main",
     ]
     outputs = [
       "${root_build_dir}/{{source_file_part}}",
     ]
     deps = [
       ":nacl_helper_nonsfi_unittests_main",
     ]
   }
 }