Add a gyp/gn variable for whether to use iLBC or not

webrtc/build/common.gypi

 # Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 # This file contains common settings for building WebRTC components.
 
 {
   # Nesting is required in order to use variables for setting other variables.
   'variables': {
     'variables': {
       'variables': {
         'variables': {
           # This will already be set to zero by supplement.gypi
           'build_with_chromium%': 1,
         },
         'build_with_chromium%': '<(build_with_chromium)',
 
+        # Enable to use the Mozilla internal settings.
+        'build_with_mozilla%': 0,
+
         'conditions': [
           ['build_with_chromium==1', {
             'webrtc_root%': '<(DEPTH)/third_party/webrtc',
             'apk_tests_path%': '<(DEPTH)/third_party/webrtc/build/apk_tests_noop.gyp',
             'modules_java_gyp_path%': '<(DEPTH)/third_party/webrtc/modules/modules_java_chromium.gyp',
           }, {
             'webrtc_root%': '<(DEPTH)/webrtc',
             'apk_tests_path%': '<(DEPTH)/webrtc/build/apk_tests.gyp',
             'modules_java_gyp_path%': '<(DEPTH)/webrtc/modules/modules_java.gyp',
           }],
         ],
       },
       'build_with_chromium%': '<(build_with_chromium)',
+      'build_with_mozilla%': '<(build_with_mozilla)',
       'webrtc_root%': '<(webrtc_root)',
       'apk_tests_path%': '<(apk_tests_path)',
       'modules_java_gyp_path%': '<(modules_java_gyp_path)',
       'webrtc_vp8_dir%': '<(webrtc_root)/modules/video_coding/codecs/vp8',
       'webrtc_vp9_dir%': '<(webrtc_root)/modules/video_coding/codecs/vp9',
       'include_opus%': 1,
       'opus_dir%': '<(DEPTH)/third_party/opus',
 
-      # Enable to use the Mozilla internal settings.
-      'build_with_mozilla%': 0,
+      # Include the iLBC audio codec?
+      'conditions': [
+        ['build_with_chromium==1 or build_with_mozilla==1', {
+          'include_ilbc%': 0,
+        }, {
+          'include_ilbc%': 1,
+        }],
+      ],
     },
     'build_with_chromium%': '<(build_with_chromium)',
     'build_with_mozilla%': '<(build_with_mozilla)',
     'webrtc_root%': '<(webrtc_root)',
     'apk_tests_path%': '<(apk_tests_path)',
     'modules_java_gyp_path%': '<(modules_java_gyp_path)',
     'webrtc_vp8_dir%': '<(webrtc_vp8_dir)',
     'webrtc_vp9_dir%': '<(webrtc_vp9_dir)',
+    'include_ilbc%': '<(include_ilbc)',
     'include_opus%': '<(include_opus)',
     'rtc_relative_path%': 1,
     'external_libraries%': '0',
     'json_root%': '<(DEPTH)/third_party/jsoncpp/source/include/',
     # openssl needs to be defined or gyp will complain. Is is only used when
     # when providing external libraries so just use current directory as a
     # placeholder.
     'ssl_root%': '.',
 
     # The Chromium common.gypi we use treats all gyp files without
@@ skipping 387 matching lines @@
           # of a more specific macro.
           'defines': [
             'WEBRTC_POSIX',
           ],
         }],
       ],
     },
   }, # target_defaults
 }