Finalize the support for building WebRTC library for iOS with bitcode

webrtc/build/ios/BUILD.gn

Index: webrtc/build/ios/BUILD.gn
diff --git a/webrtc/build/ios/BUILD.gn b/webrtc/build/ios/BUILD.gn
deleted file mode 100644
index 219617cb1706bc3afcce2620dded63ff1721186d..0000000000000000000000000000000000000000
--- a/webrtc/build/ios/BUILD.gn
+++ /dev/null
@@ -1,24 +0,0 @@
-# Copyright (c) 2016 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 is only meant to be included on iOS.
-assert(is_ios)
-
-declare_args() {
-  # Enabling this option makes clang compile to an intermediate
-  # representation, and not to native code. This is preferred when
-  # including WebRTC in apps that will be sent to Apple's App Store
-  # and required for apps that run on watchOS or tvOS.
-  rtc_ios_enable_bitcode = false
-}
-
-config("rtc_ios_common_config") {
-  if (rtc_ios_enable_bitcode) {
-    cflags = [ "-fembed-bitcode" ]
-  }
-}