This effects local swift development only and is needed now to use -enable-ossa-modules in local tests that
import Synchronization and Distributed which are non-ossa.
Type annotations for instruction operands are omitted, e.g.
```
%3 = struct $S(%1, %2)
```
Operand types are redundant anyway and were only used for sanity checking in the SIL parser.
But: operand types _are_ printed if the definition of the operand value was not printed yet.
This happens:
* if the block with the definition appears after the block where the operand's instruction is located
* if a block or instruction is printed in isolation, e.g. in a debugger
The old behavior can be restored with `-Xllvm -sil-print-types`.
This option is added to many existing test files which check for operand types in their check-lines.
As with the lexical flag, when creating an alloc_stack corresponding to
an alloc_box, transfer the var_decl flag from any begin_borrow users of
the box.
