virtual-device: Make possible to inject sleep events while verifying/identifying

Each command should be separated by SLEEP to be considered as something
we want to perform during the current operation, otherwise will be used
by next operation consuming it.

libfprint/drivers/virtual-device-storage.c

@@ -69,10 +69,14 @@ dev_identify (FpDevice *dev)
                                             &idx))
         match = g_ptr_array_index (prints, idx);
 
-      fpi_device_identify_report (dev,
-                                  match,
-                                  new_scan,
-                                  NULL);
+      if (!self->match_reported)
+        {
+          self->match_reported = TRUE;
+          fpi_device_identify_report (dev,
+                                      match,
+                                      new_scan,
+                                      NULL);
+        }
     }
   else if (error && error->domain == FP_DEVICE_RETRY)
     {
@@ -83,6 +87,10 @@ dev_identify (FpDevice *dev)
                                            FP_FINGER_STATUS_NONE,
                                            FP_FINGER_STATUS_PRESENT);
 
+  if (should_wait_to_sleep (self, scan_id, error))
+    return;
+
+  self->match_reported = FALSE;
   fpi_device_identify_complete (dev, g_steal_pointer (&error));
 }