Reland of GN: Add BUILD.gn files for webrtc/{api,media,libjingle,p2p,pc}

webrtc/libjingle/xmllite/BUILD.gn

-# Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
+# 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")
 
-source_set("bitrate_controller") {
+group("xmllite") {
+  deps = [
+    ":rtc_xmllite",
+  ]
+}
+
+source_set("rtc_xmllite") {
   sources = [
-    "bitrate_controller_impl.cc",
-    "bitrate_controller_impl.h",
-    "include/bitrate_allocator.h",
-    "include/bitrate_controller.h",
-    "send_side_bandwidth_estimation.cc",
-    "send_side_bandwidth_estimation.h",
+    "qname.cc",
+    "qname.h",
+    "xmlbuilder.cc",
+    "xmlbuilder.h",
+    "xmlconstants.cc",
+    "xmlconstants.h",
+    "xmlelement.cc",
+    "xmlelement.h",
+    "xmlnsstack.cc",
+    "xmlnsstack.h",
+    "xmlparser.cc",
+    "xmlparser.h",
+    "xmlprinter.cc",
+    "xmlprinter.h",
   ]
 
-  if (is_win) {
-    cflags = [
-      # TODO(jschuh): Bug 1348: fix this warning.
-      "/wd4267",  # size_t to int truncations
+  deps = [
+    "../../base:rtc_base",
+  ]
+
+  if (rtc_build_expat) {
+    deps += [ "//third_party/expat" ]
+    public_deps = [
+      "//third_party/expat",
     ]
   }
 
   configs += [ "../..:common_config" ]
   public_configs = [ "../..:common_inherited_config" ]
 
-  if (is_clang) {
+  if (!build_with_chromium && is_clang) {
     # Suppress warnings from Chrome's Clang plugins.
     # See http://code.google.com/p/webrtc/issues/detail?id=163 for details.
     configs -= [ "//build/config/clang:find_bad_constructs" ]
   }
-
-  deps = [
-    "../../system_wrappers",
-  ]
 }