mac ninja: Support LD_RUNPATH_SEARCH_PATHS.

test/mac/rpath/test.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': 'default_rpath',
+      'type': 'shared_library',
+      'sources': [ 'file.c' ],
+    },
+    {
+      'target_name': 'explicit_rpath',
+      'type': 'shared_library',
+      'sources': [ 'file.c' ],
+      'xcode_settings': {
+        'LD_RUNPATH_SEARCH_PATHS': ['@executable_path/.'],
+      },
+    },
+    {
+      'target_name': 'explicit_rpaths_escaped',
+      'type': 'shared_library',
+      'sources': [ 'file.c' ],
+      'xcode_settings': {
+        # Xcode requires spaces to be escaped, else it ends up adding two
+        # independent rpaths.
+        'LD_RUNPATH_SEARCH_PATHS': ['First\\ rpath', 'Second\\ rpath'],
+      },
+    },
+    {
+      'target_name': 'explicit_rpaths_bundle',
+      'product_name': 'My Framework',
+      'type': 'shared_library',
+      'mac_bundle': 1,
+      'sources': [ 'file.c' ],
+      'xcode_settings': {
+        'LD_RUNPATH_SEARCH_PATHS': ['@loader_path/.'],
+      },
+    },
+    {
+      'target_name': 'executable',
+      'type': 'executable',
+      'sources': [ 'main.c' ],
+      'xcode_settings': {
+        'LD_RUNPATH_SEARCH_PATHS': ['@executable_path/.'],
+      },
+    },
+  ],
+}