Show a 'remember me' checkbox in the web-app when connecting to a host that supports pairing.

remoting/client/plugin/chromoting_instance.cc

Index: remoting/client/plugin/chromoting_instance.cc
diff --git a/remoting/client/plugin/chromoting_instance.cc b/remoting/client/plugin/chromoting_instance.cc
index 993e887f2b17a6ce40b41a9d3a7ad94023c35c3e..3cbdfec18f37b5f9c3b90132113fa4fa1d9efdfe 100644
--- a/remoting/client/plugin/chromoting_instance.cc
+++ b/remoting/client/plugin/chromoting_instance.cc
@@ -506,6 +506,7 @@ void ChromotingInstance::SetCapabilities(const std::string& capabilities) {
 }
 
 void ChromotingInstance::FetchSecretFromDialog(
+    bool pairing_supported,
     const protocol::SecretFetchedCallback& secret_fetched_callback) {
   // Once the Session object calls this function, it won't continue the
   // authentication until the callback is called (or connection is canceled).
@@ -513,11 +514,13 @@ void ChromotingInstance::FetchSecretFromDialog(
   DCHECK(secret_fetched_callback_.is_null());
   secret_fetched_callback_ = secret_fetched_callback;
   scoped_ptr<base::DictionaryValue> data(new base::DictionaryValue());
+  data->SetBoolean("pairingSupported", pairing_supported);
   PostChromotingMessage("fetchPin", data.Pass());
 }
 
 void ChromotingInstance::FetchSecretFromString(
     const std::string& shared_secret,
+    bool pairing_supported,
     const protocol::SecretFetchedCallback& secret_fetched_callback) {
   secret_fetched_callback.Run(shared_secret);
 }