Cryptohome: Notify about error in async calls if cryptohome is not ready yet.

BUG=451148

Review URL: https://codereview.chromium.org/880303003

Cr-Commit-Position: refs/heads/master@{#313687}

chrome/browser/chromeos/login/existing_user_controller.cc

@@ -624,6 +624,10 @@ void ExistingUserController::OnAuthFailure(const AuthFailure& failure) {
     ShowTPMError();
   } else if (!online_succeeded_for_.empty()) {
     ShowGaiaPasswordChanged(online_succeeded_for_);
+  } else if (last_login_attempt_username_ == chromeos::login::kGuestUserName) {
+    // Show no errors, just re-enable input.
+    login_display_->ClearAndEnablePassword();
+    StartPublicSessionAutoLoginTimer();
   } else {
     // Check networking after trying to login in case user is
     // cached locally or the local admin account.

chromeos/cryptohome/async_method_caller.cc

@@ -308,10 +308,17 @@ class AsyncMethodCallerImpl : public AsyncMethodCaller {
         base::Bind(it->second.data_callback, return_status, return_data));
     data_callback_map_.erase(it);
   }
-
   // Registers a callback which is called when the result for AsyncXXX is ready.
   void RegisterAsyncCallback(
       Callback callback, const char* error, int async_id) {
+    if (async_id == chromeos::CryptohomeClient::kNotReadyAsyncId) {
+      base::MessageLoopProxy::current()->PostTask(
+          FROM_HERE, base::Bind(callback,
+                                false,  // return status
+                                cryptohome::MOUNT_ERROR_FATAL));
+      return;
+    }
+
     if (async_id == 0) {
       LOG(ERROR) << error;
       return;
@@ -325,6 +332,13 @@ class AsyncMethodCallerImpl : public AsyncMethodCaller {
   // Registers a callback which is called when the result for AsyncXXX is ready.
   void RegisterAsyncDataCallback(
       DataCallback callback, const char* error, int async_id) {
+    if (async_id == chromeos::CryptohomeClient::kNotReadyAsyncId) {
+      base::MessageLoopProxy::current()->PostTask(
+          FROM_HERE, base::Bind(callback,
+                                false,  // return status
+                                std::string()));
+      return;
+    }
     if (async_id == 0) {
       LOG(ERROR) << error;
       return;

chromeos/dbus/cryptohome_client.cc

@@ -20,6 +20,8 @@
 
 namespace chromeos {
 
+const int CryptohomeClient::kNotReadyAsyncId = -1;
+
 namespace {
 
 // This suffix is appended to user_id to get hash in stub implementation:
@@ -882,8 +884,10 @@ class CryptohomeClientImpl : public CryptohomeClient {
   // Handles the result of AsyncXXX methods.
   void OnAsyncMethodCall(const AsyncMethodCallback& callback,
                          dbus::Response* response) {
-    if (!response)
+    if (!response) {
+      callback.Run(kNotReadyAsyncId);
       return;
+    }
     dbus::MessageReader reader(response);
     int async_id = 0;
     if (!reader.PopInt32(&async_id)) {

chromeos/dbus/cryptohome_client.h

@@ -39,6 +39,10 @@ namespace chromeos {
 // initializes the DBusThreadManager instance.
 class CHROMEOS_EXPORT CryptohomeClient : public DBusClient {
  public:
+  // Constant that will be passed to AsyncMethodCallback to indicate that
+  // cryptohome is not ready yet.
+  static const int kNotReadyAsyncId;
+
   // A callback to handle AsyncCallStatus signals.
   typedef base::Callback<void(int async_id,
                               bool return_status,