Extracted shell_interfaces and shell_public into a separate gyp file.

services/tracing/tracing.gyp

 # Copyright 2016 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.
 
 {
   'targets': [
     {
       'target_name': 'tracing_interfaces',
       'type': 'none',
       'variables': {
@@ skipping 10 matching lines @@
       # Technically, these should be in the mojo_services.gyp, but this causes
       # a cycle since the ios generator can't have gyp files refer to each
       # other, even if the targets don't form a cycle.
       #
       # GN version: //services/tracing:lib
       'target_name': 'tracing_lib',
       'type': 'static_library',
       'dependencies': [
         'tracing_public',
         '../../mojo/mojo_edk.gyp:mojo_system_impl',
-        '../shell/shell.gyp:shell_public',
+        '../shell/shell_public.gyp:shell_public',
       ],
       'sources': [
         'trace_data_sink.cc',
         'trace_data_sink.h',
         'trace_recorder_impl.cc',
         'trace_recorder_impl.h',
         'tracing_app.cc',
         'tracing_app.h',
       ],
     },
     {
       # GN version: //mojo/services/public/cpp
       'target_name': 'tracing_public',
       'type': 'static_library',
       'dependencies': [
         'tracing_interfaces',
         '../../mojo/mojo_edk.gyp:mojo_system_impl',
-        '../shell/shell.gyp:shell_public',
+        '../shell/shell_public.gyp:shell_public',
       ],
       'sources': [
         'public/cpp/switches.cc',
         'public/cpp/switches.h',
         'public/cpp/tracing_impl.cc',
         'public/cpp/tracing_impl.h',
         'public/cpp/trace_provider_impl.cc',
         'public/cpp/trace_provider_impl.h',
       ],
     },
   ],
 }