Revert of Remove remnants of DHE support.

components/ssl_config/ssl_config_service_manager_pref.cc

Index: components/ssl_config/ssl_config_service_manager_pref.cc
diff --git a/components/ssl_config/ssl_config_service_manager_pref.cc b/components/ssl_config/ssl_config_service_manager_pref.cc
index 943723782e85af972499a2c63395800adaa44bda..0dab204ee2f47518518e1ba982e3779f8435148b 100644
--- a/components/ssl_config/ssl_config_service_manager_pref.cc
+++ b/components/ssl_config/ssl_config_service_manager_pref.cc
@@ -175,6 +175,7 @@
   BooleanPrefMember sha1_local_anchors_enabled_;
   StringPrefMember ssl_version_min_;
   StringPrefMember ssl_version_max_;
+  BooleanPrefMember dhe_enabled_;
 
   // The cached list of disabled SSL cipher suites.
   std::vector<uint16_t> disabled_cipher_suites_;
@@ -215,6 +216,8 @@
                         local_state_callback);
   ssl_version_max_.Init(ssl_config::prefs::kSSLVersionMax, local_state,
                         local_state_callback);
+  dhe_enabled_.Init(ssl_config::prefs::kDHEEnabled, local_state,
+                    local_state_callback);
 
   local_state_change_registrar_.Init(local_state);
   local_state_change_registrar_.Add(ssl_config::prefs::kCipherSuiteBlacklist,
@@ -243,6 +246,8 @@
   registry->RegisterStringPref(ssl_config::prefs::kSSLVersionMax,
                                std::string());
   registry->RegisterListPref(ssl_config::prefs::kCipherSuiteBlacklist);
+  registry->RegisterBooleanPref(ssl_config::prefs::kDHEEnabled,
+                                default_config.dhe_enabled);
 }
 
 net::SSLConfigService* SSLConfigServiceManagerPref::Get() {
@@ -290,6 +295,7 @@
     config->version_max = version_max;
   }
   config->disabled_cipher_suites = disabled_cipher_suites_;
+  config->dhe_enabled = dhe_enabled_.GetValue();
 }
 
 void SSLConfigServiceManagerPref::OnDisabledCipherSuitesChange(