ninja/mac: Don't link c-file-only targets to libstdc++

test/no-cpp/src/test.gyp

+# Copyright (c) 2013 Google Inc. 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': 'no_cpp',
+      'type': 'executable',
+      'sources': [ 'empty-main.c' ],
+    },
+    # A static_library with a cpp file and a linkable with only .c files
+    # depending on it causes a linker error:
+    {
+      'target_name': 'cpp_lib',
+      'type': 'static_library',
+      'sources': [ 'f.cc' ],
+    },
+    {
+      'target_name': 'no_cpp_dep_on_cc_lib',
+      'type': 'executable',
+      'dependencies': [ 'cpp_lib' ],
+      'sources': [ 'call-f-main.c' ],
+    },
+  ],
+}