chromeos: Wait for service to be available when getting system salt

chromeos/dbus/fake_cryptohome_client.h

Index: chromeos/dbus/fake_cryptohome_client.h
diff --git a/chromeos/dbus/fake_cryptohome_client.h b/chromeos/dbus/fake_cryptohome_client.h
index 4f045ec68d80338948ea60fa2042037fd813e5a2..3c960e8f4ccb1f9dc46150dd8a0fe9878748fb27 100644
--- a/chromeos/dbus/fake_cryptohome_client.h
+++ b/chromeos/dbus/fake_cryptohome_client.h
@@ -23,6 +23,8 @@ class CHROMEOS_EXPORT FakeCryptohomeClient : public CryptohomeClient {
       const AsyncCallStatusHandler& handler,
       const AsyncCallStatusWithDataHandler& data_handler) OVERRIDE;
   virtual void ResetAsyncCallStatusHandlers() OVERRIDE;
+  virtual void WaitForServiceToBeAvailable(
+      const WaitForServiceToBeAvailableCallback& callback) OVERRIDE;
   virtual void IsMounted(const BoolDBusMethodCallback& callback) OVERRIDE;
   virtual bool Unmount(bool* success) OVERRIDE;
   virtual void AsyncCheckKey(const std::string& username,
@@ -151,6 +153,10 @@ class CHROMEOS_EXPORT FakeCryptohomeClient : public CryptohomeClient {
       const std::string& payload,
       const BoolDBusMethodCallback& callback) OVERRIDE;
 
+  // Changes the behavior of WaitForServiceToBeAvailable(). This method runs
+  // pending callbacks if is_available is true.
+  void SetServiceIsAvailable(bool is_available);
+
   // Sets the unmount result of Unmount() call.
   void set_unmount_result(bool result) {
     unmount_result_= result;
@@ -169,12 +175,16 @@ class CHROMEOS_EXPORT FakeCryptohomeClient : public CryptohomeClient {
   void ReturnAsyncMethodResultInternal(const AsyncMethodCallback& callback,
                                        bool returns_data);
 
+  bool service_is_available_;
   int async_call_id_;
   AsyncCallStatusHandler async_call_status_handler_;
   AsyncCallStatusWithDataHandler async_call_status_data_handler_;
   int tpm_is_ready_counter_;
   bool unmount_result_;
 
+  std::vector<WaitForServiceToBeAvailableCallback>
+      pending_wait_for_service_to_be_available_callbacks_;
+
   // A stub store for InstallAttributes, mapping an attribute name to the
   // associated data blob. Used to implement InstallAttributesSet and -Get.
   std::map<std::string, std::vector<uint8> > install_attrs_;