The CPS may ask for sentencing on the first matter (whichever it is) be postponed until the sentencing date for the second so that the two may be dealt with together.
Violent disorder is the more serious offence and any sentence imposed will take precedence over the Criminal Damage matter. The most likely scenario is:
Violent Disorder – custody. Criminal Damage – custody consecutive.
There is a possibility that the judge (or magistrates) could be persuaded to impose a concurrent sentence, particularly if the Criminal Damage would not normally, by itself, attract custody.
There is little or no likelihood of a community order being made for the Criminal Damage which is to run after any custodial sentence for the Violent Disorder is served. It is not good sentencing practice.
Sorry to be a bit vague, but there are a number of options available.