GN Templates: Move common_config to the template.

webrtc/build/webrtc.gni

 # 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/arm.gni")
 import("//build/config/features.gni")
@@ skipping 143 matching lines @@
 ###############################################################################
 # Templates
 #
 
 # Points to //webrtc/ in webrtc stand-alone or to //third_party/webrtc/ in
 # chromium.
 # We need absolute paths for all configs in templates as they are shared in
 # different subdirectories.
 webrtc_root = get_path_info("../", "abspath")
 
+rtc_common_config = webrtc_root + ":common_config"

[kjellander_webrtc, 2016/09/05 06:50:28]

Let's document this one properly. Something like this:

# Global configuration that should be applied to all WebRTC targets. You
normally shouldn't need to
# include this in your target as it's automatically included when using the
rtc_* templates.
# It sets defines, include paths and compilation warnings accordingly, both for
WebRTC
# stand-alone builds and for the scenario when WebRTC native code is built as
part of Chromium.

+
 # Common configs to remove or add in all rtc targets.
 rtc_remove_configs = []
-rtc_add_configs = []
+rtc_add_configs = [ rtc_common_config ]
 
 set_defaults("rtc_test") {
-  configs = []
+  configs = rtc_add_configs
   suppressed_configs = []
 }
 
 set_defaults("rtc_source_set") {
-  configs = []
+  configs = rtc_add_configs
   suppressed_configs = []
 }
 
 set_defaults("rtc_executable") {
-  configs = []
+  configs = rtc_add_configs
   suppressed_configs = []
 }
 
 set_defaults("rtc_static_library") {
-  configs = []
+  configs = rtc_add_configs
   suppressed_configs = []
 }
 
 template("rtc_test") {
   test(target_name) {
     forward_variables_from(invoker,
                            "*",
                            [
                              "configs",
                              "suppressed_configs",
                            ])
     configs += invoker.configs
-    configs += rtc_add_configs
     configs -= rtc_remove_configs
     configs -= invoker.suppressed_configs
   }
 }
 
 template("rtc_source_set") {
   source_set(target_name) {
     forward_variables_from(invoker,
                            "*",
                            [
                              "configs",
                              "suppressed_configs",
                            ])
     configs += invoker.configs
-    configs += rtc_add_configs
     configs -= rtc_remove_configs
     configs -= invoker.suppressed_configs
   }
 }
 
 template("rtc_executable") {
   executable(target_name) {
     forward_variables_from(invoker,
                            "*",
                            [
                              "deps",
                              "configs",
                              "suppressed_configs",
                            ])
     configs += invoker.configs
-    configs += rtc_add_configs
     configs -= rtc_remove_configs
     configs -= invoker.suppressed_configs
     deps = [
       "//build/config/sanitizers:deps",
     ]
     deps += invoker.deps
   }
 }
 
 template("rtc_static_library") {
   static_library(target_name) {
     forward_variables_from(invoker,
                            "*",
                            [
                              "configs",
                              "suppressed_configs",
                            ])
     configs += invoker.configs
-    configs += rtc_add_configs
     configs -= rtc_remove_configs
     configs -= invoker.suppressed_configs
   }
 }