swift234

stdlib: rename mapping sequence and collection wrappers to a common naming convention

  struct ReverseIndex<Base : BidirectionalIndexType> { ... }
  struct ReverseRandomAccessIndex<Base : RandomAccessIndexType> { ... }

  // Renamed from `BidirectionalReverseView`.
  struct ReverseCollection<Base : CollectionType where T.Index : BidirectionalIndexType> { ... }

  // Renamed from `RandomAccessReverseView`.
  struct ReverseRandomAccessCollection<Base : CollectionType where T.Index : RandomAccessIndexType> { ... }

Also fixed a bug (found by the new tests I added in this commit) in
LazyRandomAccessCollection.reverse(), which mistakenly returned a bidirectional
reversed collection.

Part of rdar://21429126

Swift SVN r29634