Change the canonical way to include the C macros.h to <mojo/macros.h>.

mojo/edk/system/BUILD.gn

 # Copyright 2014 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("../mojo_edk.gni")
 import("//testing/test.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
@@ skipping 101 matching lines @@
 
   mojo_edk_public_deps = [
     "mojo/edk/embedder",
     "mojo/edk/embedder:delegates",
     "mojo/edk/embedder:platform",
     "mojo/edk/platform",
     "mojo/edk/util",
   ]
 
   mojo_sdk_public_deps = [
+    "mojo/public/c:system",
     "mojo/public/c/system",
     "mojo/public/cpp/system",
   ]
 
   deps = [
     "//base",
     "//base/third_party/dynamic_annotations",
   ]
 
   allow_circular_includes_from = [ "../embedder" ]
@@ skipping 81 matching lines @@
     # TODO(vtl): Add separate test targets for this.
     "mojo/edk/util:perftests",
 
     "mojo/edk/base_edk",
     "mojo/edk/base_edk:test_base_edk",
     "mojo/edk/system/test",
     "mojo/edk/system/test:perf",
     "mojo/edk/test:test_support",
   ]
 }