Pass slot id to Shill for manually configured WiFi with EAP-TLS.

chrome/browser/chromeos/options/cert_library.cc

Index: chrome/browser/chromeos/options/cert_library.cc
diff --git a/chrome/browser/chromeos/options/cert_library.cc b/chrome/browser/chromeos/options/cert_library.cc
index 7eeea75ada20b9cdd2691bda8fbe4564c7a82f16..8c2c805656c4cc7b79ea10c0bb5b64312727eb13 100644
--- a/chrome/browser/chromeos/options/cert_library.cc
+++ b/chrome/browser/chromeos/options/cert_library.cc
@@ -149,6 +149,10 @@ bool CertLibrary::IsHardwareBacked() const {
   return CertLoader::Get()->IsHardwareBacked();
 }
 
+std::string CertLibrary::GetTPMSlotID() const {
+  return base::IntToString(CertLoader::Get()->TPMTokenSlotID());
+}
+
 int CertLibrary::NumCertificates(CertType type) const {
   const net::CertificateList& cert_list = GetCertificateListForType(type);
   return static_cast<int>(cert_list.size());