Using realpath instead of android_src in Android webview

unpack_lib_posix.gypi

 # Copyright 2014 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.
 
 # This action takes an archive (.a) file and unpacks it unto object (.o) files.
 # The following input gyp variables are required:
 #   unpack_lib_output_dir, the output directory of extracted object file
 #   unpack_lib_name, the object file to be extracted.
 #   unpack_lib_search_path_list, a list of paths to search for the library.
 #   it must be ['-a', 'path_name1', '-a', 'path_name2'...]
@@ skipping 12 matching lines @@
 # It unpacks the first existing library in 'unpack_lib_search_path_list', and
 # extracts 'offsets.o' to 'output' directory.
 
 {
   'actions': [
     {
       'variables' : {
         'ar_cmd': [],
         'conditions': [
           ['android_webview_build==1', {
-            'ar_cmd': ['-r', '<(android_src)/$($(GYP_VAR_PREFIX)TARGET_AR)'],
+            'ar_cmd': ['-r', '$(realpath $($(GYP_VAR_PREFIX)TARGET_AR))'],
           }],
         ],
       },
       'action_name': 'unpack_lib_posix',
       'inputs': [
         'unpack_lib_posix.sh',
       ],
       'outputs': [
         '<(unpack_lib_output_dir)/<(unpack_lib_name)',
       ],
       'action': [
         '<(DEPTH)/third_party/libvpx/unpack_lib_posix.sh',
         '-d', '<(unpack_lib_output_dir)',
         '-f', '<(unpack_lib_name)',
         '<@(unpack_lib_search_path_list)',
         '<@(ar_cmd)',
       ],
       'process_output_as_sources': 1,
     },
   ],
 }