YAML: Add an optional 'flow' field to the mapping trait to allow flow mapping output. 

This patch adds an optional 'flow' field to the MappingTrait
class so that yaml IO will be able to output flow mappings.

Reviewers: Justin Bogner

Differential Revision: http://reviews.llvm.org/D9450


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236456 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed