Make gn check //mojo/* pass on linux and android

mojo/shell/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("//build/config/ui.gni")
 import("//mojo/public/mojo.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 
 # We don't support building in the component build since mojo apps are
 # inherently components.
@@ skipping 46 matching lines @@
     "dynamic_service_runner.h",
     "in_process_dynamic_service_runner.cc",
     "in_process_dynamic_service_runner.h",
   ]
 
   deps = [
     "//base",
     "//mojo/gles2",
     "//mojo/public/cpp/system",
   ]
+
+  # This target has to include the public thunk headers, which generally
+  # shouldn't be included without picking an implementation. We are providing
+  # the implementation but the thunk header target cannot declare that we are
+  # permitted to include it since it's in the public SDK and we are not.
+  # Suppress include checking so we can still check the rest of the targets in
+  # this file.
+  check_includes = false
 }
 
 source_set("lib") {
   sources = [
     "app_child_process.cc",
     "app_child_process.h",
     "app_child_process_host.cc",
     "app_child_process_host.h",
     "child_process.cc",
     "child_process.h",
@@ skipping 57 matching lines @@
       "network_application_loader.cc",
       "network_application_loader.h",
     ]
 
     deps += [
       "//mojo/services/gles2",
       "//mojo/services/native_viewport:lib",
       "//mojo/services/network:lib",
     ]
   }
+
+  # This target includes some files behind #ifdef OS... guards. Since gn is not
+  # smart enough to understand preprocess includes, it does complains about
+  # these includes when not using the build files for that OS. Suppress checking
+  # so we can enable checking for the rest of the targets in this file.
+  # TODO: Might be better to split the files with OS-specific includes out to a
+  # separate source_set so we can leave checking on for the rest of the target.
+  check_includes = false
 }
 
 if (is_android) {
   generate_jni("jni_headers") {
     sources = [
       "android/apk/src/org/chromium/mojo_shell_apk/MojoMain.java",
     ]
     jni_package = "mojo"
   }
 
@@ skipping 179 matching lines @@
 
     deps -= [
       ":lib",
       ":external_application_registrar_connection",
       ":external_application_registrar_bindings",
       "//mojo/shell/domain_socket",
       "//mojo/shell/domain_socket:tests",
     ]
   }
 }