Remove screen_orientation_messages.h.

content/common/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/features.gni")
 import("//build/config/ui.gni")
 import("//media/media_options.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//ppapi/features/features.gni")
 import("//sandbox/features.gni")
@@ skipping 278 matching lines @@
     "sandbox_linux/sandbox_init_linux.cc",
     "sandbox_linux/sandbox_linux.cc",
     "sandbox_linux/sandbox_linux.h",
     "sandbox_linux/sandbox_seccomp_bpf_linux.cc",
     "sandbox_linux/sandbox_seccomp_bpf_linux.h",
     "sandbox_mac.h",
     "sandbox_mac.mm",
     "sandbox_win.cc",
     "sandbox_win.h",
     "savable_subframe.h",
-    "screen_orientation_messages.h",
     "send_zygote_child_ping_linux.cc",
     "service_manager/embedded_service_runner.cc",
     "service_manager/embedded_service_runner.h",
     "service_manager/service_manager_connection_impl.cc",
     "service_manager/service_manager_connection_impl.h",
     "service_worker/embedded_worker_messages.h",
     "service_worker/embedded_worker_settings.h",
     "service_worker/embedded_worker_start_params.cc",
     "service_worker/embedded_worker_start_params.h",
     "service_worker/service_worker_client_info.cc",
@@ skipping 318 matching lines @@
     "//url/mojo:url_mojom_origin",
   ]
 
   overridden_deps = [ "//ipc:mojom" ]
   component_deps = [ "//ipc" ]
 
   export_class_attribute = "CONTENT_EXPORT"
   export_define = "CONTENT_IMPLEMENTATION=1"
   export_header = "content/common/content_export.h"
 }