Decoupling objc_videotoolbox from non Obj-C code

webrtc/sdk/BUILD.gn

 # Copyright 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.
 
 import("../webrtc.gni")
 if (is_ios) {
@@ skipping 688 matching lines @@
 
       if (!build_with_chromium && is_clang) {
         # Suppress warnings from the Chromium Clang plugin
         # (bugs.webrtc.org/163).
         suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
       }
 
       libs = [ "CoreVideo.framework" ]
     }
 
+    rtc_static_library("video_toolbox_cc") {
+      visibility = [ ":*" ]
+      sources = [
+        "objc/Framework/Classes/VideoToolbox/helpers.cc",
+        "objc/Framework/Classes/VideoToolbox/helpers.h",
+        "objc/Framework/Classes/VideoToolbox/nalu_rewriter.cc",
+        "objc/Framework/Classes/VideoToolbox/nalu_rewriter.h",
+      ]
+      deps = [
+        "../common_video",
+        "../modules:module_api",
+        "../modules/video_coding:webrtc_h264",
+        "../rtc_base:rtc_base_approved",
+      ]
+      if (!build_with_chromium && is_clang) {
+        # Suppress warnings from the Chromium Clang plugin
+        # (bugs.webrtc.org/163).
+        suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
+      }
+    }
+
     rtc_static_library("videotoolbox_objc") {
       sources = [
         "objc/Framework/Classes/VideoToolbox/RTCVideoDecoderH264.mm",
         "objc/Framework/Classes/VideoToolbox/RTCVideoEncoderH264.mm",
-        "objc/Framework/Classes/VideoToolbox/helpers.cc",
-        "objc/Framework/Classes/VideoToolbox/helpers.h",
-        "objc/Framework/Classes/VideoToolbox/nalu_rewriter.cc",
-        "objc/Framework/Classes/VideoToolbox/nalu_rewriter.h",
         "objc/Framework/Classes/VideoToolbox/objc_video_decoder_factory.h",
         "objc/Framework/Classes/VideoToolbox/objc_video_decoder_factory.mm",
         "objc/Framework/Classes/VideoToolbox/objc_video_encoder_factory.h",
         "objc/Framework/Classes/VideoToolbox/objc_video_encoder_factory.mm",
         "objc/Framework/Headers/WebRTC/RTCVideoFrameBuffer.h",
       ]
 
       configs += [ "..:common_objc" ]
 
       deps = [
         ":common_objc",
         ":video_objc",
+        ":video_toolbox_cc",
         ":videotracksource_objc",
         "../api/video_codecs:video_codecs_api",
         "../common_video",
         "../media:rtc_media",
         "../media:rtc_media_base",
         "../modules:module_api",
         "../modules/video_coding:video_coding_utility",
         "../modules/video_coding:webrtc_h264",
         "../rtc_base:rtc_base_approved",
         "../system_wrappers",
@@ skipping 17 matching lines @@
         public_deps = [
           "$rtc_libyuv_dir",
         ]
       } else {
         # Need to add a directory normally exported by libyuv.
         include_dirs = [ "$rtc_libyuv_dir/include" ]
       }
     }
   }
 }