Add gn target rtc_task_runner.

webrtc/base/BUILD.gn

 # Copyright (c) 2014 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("//build/config/crypto.gni")
 import("//build/config/ui.gni")
@@ skipping 330 matching lines @@
   if (is_win && is_clang) {
     cflags = [
       # Disable warnings failing when compiling with Clang on Windows.
       # https://bugs.chromium.org/p/webrtc/issues/detail?id=5366
       "-Wno-sign-compare",
       "-Wno-missing-braces",
     ]
   }
 }
 
+# TODO(nisse): This target is temporarily split out, to aid moving the
+# code over to Chrome. It should be deleted from webrtc soon.
+rtc_static_library("rtc_task_runner") {
+  sources = [
+    "task.cc",
+    "task.h",
+    "taskparent.cc",
+    "taskparent.h",
+    "taskrunner.cc",
+    "taskrunner.h",
+  ]
+}
+
 rtc_static_library("rtc_base") {
   cflags = []
   cflags_cc = []
   libs = []
   defines = []
   deps = [
     "..:webrtc_common",
   ]
   public_deps = [
     ":rtc_base_approved",
+    ":rtc_task_runner",
   ]
   public_configs = []
 
   all_dependent_configs = [ ":rtc_base_all_dependent_config" ]
 
   sources = [
     "applefilesystem.mm",
     "asyncinvoker-inl.h",
     "asyncinvoker.cc",
     "asyncinvoker.h",
@@ skipping 85 matching lines @@
     "ssladapter.cc",
     "ssladapter.h",
     "sslfingerprint.cc",
     "sslfingerprint.h",
     "sslidentity.cc",
     "sslidentity.h",
     "sslstreamadapter.cc",
     "sslstreamadapter.h",
     "stream.cc",
     "stream.h",
-    "task.cc",
-    "task.h",
-    "taskparent.cc",
-    "taskparent.h",
-    "taskrunner.cc",
-    "taskrunner.h",
     "thread.cc",
     "thread.h",
   ]
 
   # TODO(henrike): issue 3307, make rtc_base build with the Chromium default
   # compiler settings.
   suppressed_configs += [ "//build/config/compiler:chromium_code" ]
   configs += [ "//build/config/compiler:no_chromium_code" ]
   if (!is_win) {
     cflags += [ "-Wno-uninitialized" ]
@@ skipping 416 matching lines @@
 
 if (is_android) {
   android_library("base_java") {
     java_files = [
       "java/src/org/webrtc/Logging.java",
       "java/src/org/webrtc/Size.java",
       "java/src/org/webrtc/ThreadUtils.java",
     ]
   }
 }