Remove the 'ios_use_webrtc' build flag hack.

BUILD.gn

 # 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.
 
 # This is the root build file for GN. GN will start processing by loading this
 # file, and recursively load all dependencies until all dependencies are either
 # resolved or known not to exist (which will cause the build to fail). So if
 # you add a new build file, there must be some path of dependencies from this
 # file to your new one or GN won't know about it.
 
 import("//build/config/features.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("//build/config/ui.gni")
 import("//build_overrides/v8.gni")
-import("//build_overrides/webrtc.gni")
 import("//media/media_options.gni")
 import("//third_party/openh264/openh264_args.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
 }
 
 declare_args() {
   # A list of extra dependencies to add to the root target. This allows a
   # checkout to add additional targets without explicitly changing any checked-
@@ skipping 166 matching lines @@
       "//third_party/catapult/telemetry:bitmaptools($host_toolchain)",
       "//third_party/smhasher:pmurhash",
       "//tools/imagediff($host_toolchain)",
       "//ui/display:display_unittests",
       "//ui/events:events_unittests",
       "//ui/gl:gl_unittests",
       "//ui/touch_selection:ui_touch_selection_unittests",
     ]
   } else {
     deps += [
+      #"//ios/chrome:ios_chrome_unittests", TODO(GYP)
+      #"//ios/chrome/app", TODO(GYP)
+      #"//ios/chrome/browser", TODO(GYP)
+      "//ios/chrome/common",
       "//ios/net:ios_net_unittests",
+      "//ios/public/provider/chrome/browser",
       "//ios/public/provider/web",
       "//ios/testing:ocmock_support_unittest",
       "//ios/web:ios_web_unittests",
       "//ios/web/shell:ios_web_shell",
     ]
-
-    if (ios_use_webrtc) {
-      deps += [
-        "//ios/chrome:ios_chrome_unittests",
-        "//ios/chrome/app",
-        "//ios/chrome/browser",
-        "//ios/chrome/common",
-        "//ios/public/provider/chrome/browser",
-      ]
-    }
   }
 
   deps += root_extra_deps
 
   if (enable_extensions) {
     deps += [ "//extensions/shell:app_shell_unittests" ]
   }
 
   if (enable_media_router) {
     deps += [ "//chrome/browser/media/router" ]
@@ skipping 642 matching lines @@
       ]
 
       if (target_cpu == "x86") {
         deps += [ "//chrome/tools/crash_service:crash_service_win64" ]
       }
     } else {
       deps += [ "//breakpad:minidump_stackwalk($host_toolchain)" ]
     }
   }
 }