Provide scheduler_ptr to _ScheduleFuncWithAutoInline

[parkske]

The ambient_scheduler may not be the desired scheduler to schedule
functions on, but _ScheduleFuncWithAutoInline does not offer any
other option. Provide a means to select a desired scheduler and
fall back to the ambient scheduler if not specified.

Related issue: #1595

[ghost]

All CLA requirements met.

[parkske]

@BillyONeal could you have a look? We ran into this when trying to pin tasks to a specific scheduler. Unsure if we're missing a case when the workflow requires use of the Ambient scheduler.

[BillyONeal]

@BillyONeal could you have a look? We ran into this when trying to pin tasks to a specific scheduler. Unsure if we're missing a case when the workflow requires use of the Ambient scheduler.

I am no longer directly affiliated with cpprestsdk. If I still were I would be concerned about making API changes to pplx parts unless they can be exactly replicated in ppl, because pplx's API contract is 'exactly ppl but works on other platforms'.

[barcharcraz]

Can you verify what ppl tasks does natively in this situation?

[parkske]

Can you verify what ppl tasks does natively in this situation?

@barcharcraz Is there source available to examine? Or are you asking if I can compile a program against ppl with similar functionality and examine the scheduler tasks are run on?