Handle certificate generation errors in chromoting host.

remoting/host/remoting_me2me_host.cc

Index: remoting/host/remoting_me2me_host.cc
diff --git a/remoting/host/remoting_me2me_host.cc b/remoting/host/remoting_me2me_host.cc
index 6dcad1bd8b18cb7069577d009b931c3596b9da23..1e518af2dbf6c976db7cae98cb99b56c11b58845 100644
--- a/remoting/host/remoting_me2me_host.cc
+++ b/remoting/host/remoting_me2me_host.cc
@@ -255,10 +255,17 @@ class HostProcess
 
   void CreateAuthenticatorFactory() {
     DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
+
+    std::string local_certificate = key_pair_.GenerateCertificate();
+    if (local_certificate.empty()) {
+      LOG(ERROR) << "Failed to generate host certificate.";
+      Shutdown(kHostInitializationFailed);
+      return;
+    }
+
     scoped_ptr<protocol::AuthenticatorFactory> factory(
         new protocol::Me2MeHostAuthenticatorFactory(
-            key_pair_.GenerateCertificate(),
-            *key_pair_.private_key(), host_secret_hash_));
+            local_certificate, *key_pair_.private_key(), host_secret_hash_));
     host_->SetAuthenticatorFactory(factory.Pass());
   }