Reland of Moving webrtc.gni up one level from build/

webrtc/stats/BUILD.gn

 # 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.
 
-import("../build/webrtc.gni")
+import("../webrtc.gni")
 
 group("stats") {
   public_deps = [
     ":rtc_stats",
   ]
 }
 
 rtc_static_library("rtc_stats") {
   cflags = []
   sources = [
@@ skipping 40 matching lines @@
       "../base:rtc_base_tests_main",
       "../system_wrappers:metrics_default",
       "//testing/gmock",
     ]
 
     if (is_android) {
       deps += [ "//testing/android/native_test:native_test_native_code" ]
     }
   }
 }