Roll forward to cl/340537221

Signed-off-by: hai007 <hais@google.com>

cpp/core/internal/mediums/webrtc.cc

@@ -42,6 +42,10 @@ WebRtc::~WebRtc() {
   Disconnect();
 }
 
+const std::string WebRtc::GetDefaultCountryCode() {
+  return medium_.GetDefaultCountryCode();
+}
+
 bool WebRtc::IsAvailable() { return medium_.IsValid(); }
 
 bool WebRtc::IsAcceptingConnections() {

cpp/core/internal/mediums/webrtc.h

@@ -44,6 +44,10 @@ class WebRtc {
   WebRtc();
   ~WebRtc();
 
+  // Gets the default two-letter country code associated with current locale.
+  // For example, en_US locale resolves to "US".
+  const std::string GetDefaultCountryCode();
+
   // Returns if WebRtc is available as a medium for nearby to transport data.
   // Runs on @MainThread.
   bool IsAvailable();

cpp/core/internal/webrtc_bwu_handler.cc

@@ -1,6 +1,5 @@
 #include "core/internal/webrtc_bwu_handler.h"
 
-#include <locale>
 #include <string>
 
 #include "core/internal/client_proxy.h"
@@ -61,7 +60,8 @@ ByteArray WebrtcBwuHandler::InitializeUpgradedMediumForEndpoint(
   // stop the advertising yet.
   std::string upgrade_service_id = Utils::WrapUpgradeServiceId(service_id);
 
-  LocationHint location_hint = Utils::BuildLocationHint(GetCountryCode());
+  LocationHint location_hint =
+      Utils::BuildLocationHint(webrtc_.GetDefaultCountryCode());
 
   mediums::PeerId self_id{mediums::PeerId::FromRandom()};
   if (!webrtc_.IsAcceptingConnections()) {
@@ -141,23 +141,6 @@ WebrtcBwuHandler::CreateUpgradedEndpointChannel(
 void WebrtcBwuHandler::OnEndpointDisconnect(ClientProxy* client,
                                             const std::string& endpoint_id) {}
 
-std::string WebrtcBwuHandler::GetCountryCode() {
-  std::string default_locale_name = std::locale("").name();
-
-  // locale name has a format: <lang>_<country>.<encoding>
-  int s = default_locale_name.find("_");
-  int e = default_locale_name.find(".");
-
-  if (s == -1 || e == -1) {
-    return "";
-  }
-
-  auto country_code = default_locale_name.substr(s + 1, e - s - 1);
-  std::transform(country_code.begin(), country_code.end(), country_code.begin(),
-                 std::towlower);
-  return country_code;
-}
-
 WebrtcBwuHandler::WebrtcIncomingSocket::WebrtcIncomingSocket(
     const std::string& name, mediums::WebRtcSocketWrapper socket)
     : name_(name), socket_(socket) {}

cpp/platform/api/webrtc.h

@@ -33,6 +33,10 @@ class WebRtcMedium {
 
   virtual ~WebRtcMedium() = default;
 
+  // Gets the default two-letter country code associated with current locale.
+  // For example, en_US locale resolves to "US".
+  virtual const std::string GetDefaultCountryCode() = 0;
+
   // Creates and returns a new webrtc::PeerConnectionInterface object via
   // |callback|.
   virtual void CreatePeerConnection(webrtc::PeerConnectionObserver* observer,

cpp/platform/impl/g3/webrtc.cc

@@ -32,6 +32,10 @@ void WebRtcSignalingMessenger::StopReceivingMessages() {
   env.UnregisterWebRtcSignalingMessenger(self_id_);
 }
 
+const std::string WebRtcMedium::GetDefaultCountryCode() {
+  return "US";
+}
+
 void WebRtcMedium::CreatePeerConnection(
     webrtc::PeerConnectionObserver* observer, PeerConnectionCallback callback) {
   auto& env = MediumEnvironment::Instance();

cpp/platform/impl/g3/webrtc.h

@@ -38,6 +38,8 @@ class WebRtcMedium : public api::WebRtcMedium {
   WebRtcMedium() = default;
   ~WebRtcMedium() override = default;
 
+  const std::string GetDefaultCountryCode() override;
+
   // Creates and returns a new webrtc::PeerConnectionInterface object via
   // |callback|.
   void CreatePeerConnection(webrtc::PeerConnectionObserver* observer,

cpp/platform/public/webrtc.h

@@ -47,6 +47,12 @@ class WebRtcMedium final {
   WebRtcMedium(WebRtcMedium&&) = delete;
   WebRtcMedium& operator=(WebRtcMedium&&) = delete;
 
+  // Gets the default two-letter country code associated with current locale.
+  // For example, en_US locale resolves to "US".
+  const std::string GetDefaultCountryCode() {
+    return impl_->GetDefaultCountryCode();
+  }
+
   // Creates and returns a new webrtc::PeerConnectionInterface object via
   // |callback|.
   void CreatePeerConnection(webrtc::PeerConnectionObserver* observer,