[Reland] Mojo: Eliminate duplicate C API symbols

mojo/mojo_base.gyp

 # 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.
 
 # Essential components (and their tests) that are needed to build
 # Chrome should be here.  Other components that are useful only in
 # Mojo land like mojo_shell should be in mojo.gyp.
 {
-  'includes': [
-    'mojo_variables.gypi',
-  ],
+  'variables': {
+    'chromium_code': 1,
+  },
   'targets': [
     {
       'target_name': 'mojo_base',
       'type': 'none',
       'dependencies': [
         # NOTE: If adding a new dependency here, please consider whether it
         # should also be added to the list of Mojo-related dependencies of
         # build/all.gyp:All on iOS, as All cannot depend on the mojo_base
         # target on iOS due to the presence of the js targets, which cause v8
         # to be built.
@@ skipping 16 matching lines @@
     {
       # GN version: //mojo/common
       'target_name': 'mojo_common_lib',
       'type': '<(component)',
       'defines': [
         'MOJO_COMMON_IMPLEMENTATION',
       ],
       'dependencies': [
         '../base/base.gyp:base',
         '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
-        '<(mojo_system_for_component)',
+        '../mojo/mojo_public.gyp:mojo_public_system',
       ],
       'export_dependent_settings': [
         '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
       ],
       'sources': [
         'common/common_type_converters.cc',
         'common/common_type_converters.h',
         'common/data_pipe_file_utils.cc',
         'common/data_pipe_utils.cc',
         'common/data_pipe_utils.h',
@@ skipping 17 matching lines @@
       'includes': [ 'mojom_bindings_generator_explicit.gypi' ],
     },
     {
       # GN version: //mojo/common:url_type_converters
       'target_name': 'mojo_url_type_converters',
       'type': 'static_library',
       'dependencies': [
         '../base/base.gyp:base',
         '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
         '../url/url.gyp:url_lib',
-        '<(mojo_system_for_component)',
+        '../mojo/mojo_public.gyp:mojo_public_system',
       ],
       'export_dependent_settings': [
         '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
       ],
       'sources': [
         'common/url_type_converters.cc',
         'common/url_type_converters.h',
       ],
     },
     {
@@ skipping 110 matching lines @@
             '../build/isolate.gypi',
           ],
           'sources': [
             'mojo_common_unittests.isolate',
           ],
         },
       ],
     }],
   ]
 }