Summary:
Introduces a separate target for comment manipulation.
Currently, comment manipulation is in BreakableComment.cpp.
Towards implementing comment reflowing, we want to factor out the
comment-related functionality, so it can be reused.
Start simple by just moving out getLineCommentIndentPrefix.
Patch by Krasimir Georgiev!
Reviewers: djasper
Subscribers: klimek, beanz, mgorny, modocache
Differential Revision: https://reviews.llvm.org/D25725
llvm-svn: 284573