android: Support host multilib builds.

test/android/host_32or64.gyp

+# Copyright (c) 2014 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': 'lib32or64',
+      'type': 'static_library',
+      'toolsets': [ 'host' ],
+      'sources': [
+        '32or64.c',
+      ],
+    },
+    {
+      'target_name': 'host_32or64',
+      'type': 'executable',
+      'toolsets': [ 'host' ],
+      'dependencies': [ 'lib32or64#host' ],
+      'sources': [
+        'writefile.c',
+      ],
+    },
+    {
+      'target_name': 'generate_output',
+      'type': 'none',
+      'dependencies': [ 'host_32or64#host' ],
+      'actions': [
+        {
+          'action_name': 'generate',
+          'inputs': [ '<(PRODUCT_DIR)/host_32or64' ],
+          'outputs': [ '<(PRODUCT_DIR)/host_32or64.output' ],
+          'action': [ '<@(_inputs)', '<@(_outputs)' ],
+        }
+      ],
+    },
+  ],
+}