Reset autoclick delay time to default if delay is zero

This cl fixes a edge case when users switch the autoclick
indicator flag from disabled to enabled, the autoclick delay
time could be 0. In this case, auto-reset it to default as the
autoclick settings page initialized.

Bug: 413144145
Test: manually verified on test device
Flag: com.android.server.accessibility.enable_autoclick_indicator
Change-Id: I39db9258f1851458e1edb90dbf3dee8042b4b872