This applies to callers that do not have full knowledge of the command
list state, and thus, cannot restore it should allocations cause command
list execution. Instead we reallocate a new buffer. Should not happen
often enough for this to be a concern, as it's mainly for the utility
classes.
A few StreamBuffer instances take arguments that are actually size_t,
and this will cause truncation warnings during argument forwarding
with make_unique.
Pierre Bourdon