Remove the dependency on the STRIP env variable for Android

tools/android/device_stats_monitor/device_stats_monitor.gyp

 # Copyright (c) 2012 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.
 
 {
   'targets': [
     {
       'target_name': 'device_stats_monitor',
       'type': 'none',
       'dependencies': [
         'device_stats_monitor_symbols',
       ],
       'actions': [
         {
           'action_name': 'strip_device_stats_monitor',
           'inputs': ['<(PRODUCT_DIR)/device_stats_monitor_symbols'],
           'outputs': ['<(PRODUCT_DIR)/device_stats_monitor'],
           'action': [
-            '<!(/bin/echo -n $STRIP)',
+            '<(android_strip)',
             '--strip-unneeded',
             '<@(_inputs)',
             '-o',
             '<@(_outputs)',
           ],
         },
       ],
     }, {
       'target_name': 'device_stats_monitor_symbols',
       'type': 'executable',
       'dependencies': [
         '../../../base/base.gyp:base',
       ],
       'include_dirs': [
         '../../..',
       ],
       'sources': [
         'device_stats_monitor.cc',
       ],
     },
   ],
 }