Fix generation for ninja of multiarch executable targets

test/mac/archs/test-archs-multiarch.gyp

 # Copyright (c) 2012 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': 'static_32_64',
       'type': 'static_library',
       'sources': [ 'my_file.cc' ],
@@ skipping 38 matching lines @@
     # This only needs to compile.
     {
       'target_name': 'precompiled_prefix_header_mm_32_64',
       'type': 'shared_library',
       'sources': [ 'file.mm', ],
       'xcode_settings': {
         'GCC_PREFIX_HEADER': 'header.h',
         'GCC_PRECOMPILE_PREFIX_HEADER': 'YES',
       },
     },
+    # This does not compile but should not cause generation errors.
+    {
+      'target_name': 'exe_32_64_no_sources',
+      'type': 'executable',
+      'dependencies': [
+        ':static_32_64',

[Nico, 2014/02/17 21:41:12]

(No leading ':' on local targets.)

+      ],
+      'sources': [],
+      'xcode_settings': {
+        'ARCHS': ['i386', 'x86_64'],
+      },
+    },
   ]
 }