Always use ENABLE_PLUGINS to indicate plugins support.

content/content_tests.gypi

 # Copyright (c) 2013 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.
 
 {
   'variables': {
     'layouttest_support_content_sources': [
       'public/test/layouttest_support.h',
       'public/test/nested_message_pump_android.cc',
       'public/test/nested_message_pump_android.h',
@@ skipping 1904 matching lines @@
                 'additional_input_paths': [
                   '<(PRODUCT_DIR)/icudtl.dat',
                 ],
               }],
               ['v8_use_external_startup_data==1', {
                 'additional_input_paths': [
                   '<(PRODUCT_DIR)/natives_blob.bin',
                   '<(PRODUCT_DIR)/snapshot_blob.bin',
                 ],
               }],
+              ['enable_plugins==1', {
+                'additional_bundled_libs': [
+                  '<(PRODUCT_DIR)/libppapi_tests.so',
+                ],
+              }],
             ],
           },
           'includes': [ '../build/apk_browsertest.gypi' ],
         },
         {
           # TODO(GN)
           'target_name': 'content_perftests_apk',
           'type': 'none',
           'dependencies': [
             'content.gyp:content_java',
@@ skipping 177 matching lines @@
             ],
           },
           'includes': [
             '../build/host_jar.gypi',
           ],
         },
       ],
     }],
   ],
 }