[ios] Remove the support for bitcode

According to Xcode 14 documentation [1]:

  > Xcode no longer builds bitcode by default and generates a warning
  > message if a project explicitly enables bitcode: “Building with
  > bitcode is deprecated. Please update your project and/or target
  > settings to disable bitcode.” The capability to build with bitcode
  > will be removed in a future Xcode release. IPAs that contain bitcode
  > will have the bitcode stripped before being submitted to the App
  > Store. Debug symbols for past bitcode submissions remain available
  > for download. (86118779)

[1]: https://developer.apple.com/documentation/Xcode-Release-Notes/xcode-14-release-notes

Bug: webrtc:14237
Change-Id: I39fb618409e1978f8e7b42aa71208e00ed69d85f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/267407
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Sylvain Defresne <sdefresne@chromium.org>
Cr-Commit-Position: refs/heads/main@{#37415}

docs/native-code/ios/index.md

@@ -2,9 +2,8 @@
 
 ## Development Environment
 
-In case you need to build the framework manually
-(for instance if you need to support bitcode) or you want to try out the demo application
-AppRTCMobile, follow the instructions illustrated bellow.
+In case you need to build the framework manually or you want to try out the
+demo application AppRTCMobile, follow the instructions illustrated bellow.
 
 A macOS machine is required for iOS development. While it's possible to
 develop purely from the command line with text editors, it's easiest to use
@@ -170,11 +169,6 @@ If you need a FAT `.framework`, that is, a binary that contains code for
 multiple architectures, and will work both on device and in the simulator,
 a script is available [here][framework-script]
 
-To build the framework with bitcode support, pass the `--bitcode` flag to the script like so
-
-```
-$ python tools_webrtc/ios/build_ios_libs.py --bitcode
-```
 The resulting framework can be found in out_ios_libs/.
 
 Please note that you can not ship the FAT framework binary with your app

tools_webrtc/ios/build_ios_libs.py

@@ -87,11 +87,6 @@ def _ParseArgs():
       type=int,
       default=0,
       help='Specifies a revision number to embed if building the framework.')
-  parser.add_argument('-e',
-                      '--bitcode',
-                      action='store_true',
-                      default=False,
-                      help='Compile with bitcode.')
   parser.add_argument('--verbose',
                       action='store_true',
                       default=False,
@@ -154,7 +149,7 @@ def _ParseArchitecture(architectures):
 
 def BuildWebRTC(output_dir, target_environment, target_arch, flavor,
                 gn_target_name, ios_deployment_target, libvpx_build_vp9,
-                use_bitcode, use_goma, extra_gn_args):
+                use_goma, extra_gn_args):
   gn_args = [
       'target_os="ios"',
       'ios_enable_code_signing=false',
@@ -179,8 +174,7 @@ def BuildWebRTC(output_dir, target_environment, target_arch, flavor,
   gn_args.append('rtc_libvpx_build_vp9=' +
                  ('true' if libvpx_build_vp9 else 'false'))
 
-  gn_args.append('enable_ios_bitcode=' + ('true' if use_bitcode else 'false'))
-  gn_args.append('use_lld=' + ('false' if use_bitcode else 'true'))
+  gn_args.append('use_lld=true')
   gn_args.append('use_goma=' + ('true' if use_goma else 'false'))
   gn_args.append('rtc_enable_objc_symbol_export=true')
 
@@ -228,7 +222,6 @@ def main():
     return 0
 
   gn_target_name = 'framework_objc'
-  if not args.bitcode:
   gn_args.append('enable_dsyms=true')
   gn_args.append('enable_stripping=true')
 
@@ -244,7 +237,7 @@ def main():
       lib_paths.append(lib_path)
       BuildWebRTC(lib_path, environment, arch, args.build_config,
                   gn_target_name, IOS_DEPLOYMENT_TARGET[environment],
-                  LIBVPX_BUILD_VP9, args.bitcode, args.use_goma, gn_args)
+                  LIBVPX_BUILD_VP9, args.use_goma, gn_args)
     all_lib_paths.extend(lib_paths)
 
     # Combine the slices.