Enable GN check for webrtc/{p2p,system_wrappers}

webrtc/system_wrappers/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.
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
 }
 import("../webrtc.gni")
 
 rtc_static_library("system_wrappers") {
   sources = [
     "include/aligned_array.h",
     "include/aligned_malloc.h",
     "include/atomic32.h",
     "include/clock.h",
-    "include/cpu_features_wrapper.h",
     "include/cpu_info.h",
     "include/event_wrapper.h",
-    "include/field_trial.h",
     "include/file_wrapper.h",
     "include/fix_interlocked_exchange_pointer_win.h",
-    "include/metrics.h",
     "include/ntp_time.h",
     "include/rtp_to_ntp_estimator.h",
     "include/rw_lock_wrapper.h",
     "include/sleep.h",
     "include/static_instance.h",
     "include/timestamp_extrapolator.h",
     "include/trace.h",
     "source/aligned_malloc.cc",
     "source/atomic32_win.cc",
     "source/clock.cc",
@@ skipping 19 matching lines @@
     "source/trace_posix.h",
     "source/trace_win.cc",
     "source/trace_win.h",
   ]
 
   defines = []
   libs = []
   deps = [
     "..:webrtc_common",
   ]
+  public_deps = [
+    ":cpu_features_api",
+    ":field_trial_api",
+    ":metrics_api",
+  ]
 
   if (is_android) {
     sources += [
       "include/logcat_trace_context.h",
       "source/logcat_trace_context.cc",
     ]
 
     defines += [ "WEBRTC_THREAD_RR" ]
 
     deps += [ ":cpu_features_android" ]
@@ skipping 20 matching lines @@
     sources += [ "source/atomic32_darwin.cc" ]
   }
 
   # TODO(jschuh): Bug 1348: fix this warning.
   configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
 
   if (is_win) {
     libs += [ "winmm.lib" ]
 
     cflags = [ "/wd4334" ]  # Ignore warning on shift operator promotion.
+
+    # Windows needs //webrtc/base:rtc_base due to include of webrtc/base/win32.h
+    # in source/clock.cc.
+    # TODO(kjellander): Remove (bugs.webrtc.org/6828)
+    deps += [ "../base:rtc_base" ]
   }
 
   if (is_win && is_clang) {
     # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
     suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
   }
 
   deps += [ "../base:rtc_base_approved" ]
 }
 
+rtc_source_set("cpu_features_api") {
+  sources = [
+    "include/cpu_features_wrapper.h",
+  ]
+  deps = [
+    "..:webrtc_common",
+  ]
+}
+
+rtc_source_set("field_trial_api") {
+  sources = [
+    "include/field_trial.h",
+  ]
+}
+
+rtc_source_set("metrics_api") {
+  sources = [
+    "include/metrics.h",
+  ]
+  deps = [
+    "..:webrtc_common",
+    "../base:rtc_base_approved",
+  ]
+}
+
 rtc_static_library("field_trial_default") {
   sources = [
     "include/field_trial_default.h",
     "source/field_trial_default.cc",
   ]
+  deps = [
+    ":field_trial_api",
+  ]
 }
 
 rtc_static_library("metrics_default") {
   sources = [
     "include/metrics_default.h",
     "source/metrics_default.cc",
   ]
+  deps = [
+    ":metrics_api",
+    "../base:rtc_base_approved",
+  ]
 }
 
 group("system_wrappers_default") {
   deps = [
     ":field_trial_default",
     ":metrics_default",
     ":system_wrappers",
   ]
 }
 
 if (is_android) {
   rtc_static_library("cpu_features_android") {
     sources = [
       "source/cpu_features_android.c",
     ]
 
     deps = [
       "//third_party/android_tools:cpu_features",
     ]
   }
 }
 
 if (is_linux) {
   rtc_static_library("cpu_features_linux") {
     sources = [
       "source/cpu_features_linux.c",
     ]
+    deps = [
+      ":cpu_features_api",
+    ]
   }
 }
 
 if (rtc_include_tests) {
   rtc_test("system_wrappers_unittests") {
     testonly = true
     sources = [
       "source/aligned_array_unittest.cc",
       "source/aligned_malloc_unittest.cc",
       "source/clock_unittest.cc",
       "source/event_timer_posix_unittest.cc",
       "source/metrics_default_unittest.cc",
       "source/metrics_unittest.cc",
       "source/ntp_time_unittest.cc",
       "source/rtp_to_ntp_estimator_unittest.cc",
     ]
     configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
 
     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" ]
     }
 
     deps = [
       ":metrics_default",
       ":system_wrappers",
+      "..:webrtc_common",
+      "../base:rtc_base_approved",
       "../test:test_main",
       "//testing/gtest",
     ]
 
     if (is_android) {
       deps += [ "//testing/android/native_test:native_test_support" ]
 
       shard_timeout = 900
     }
   }
 }