Summary:
This patch removes the manual byte counting in all internal Stream methods.
This is now done by the automatic byte counting provided by calling `GetWrittenBytes()`
before and after writing the data (which is automatically done for us by the `ByteDelta`
utility class).
Reviewers: #lldb, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: JDevlieghere, labath, lldb-commits
Differential Revision: https://reviews.llvm.org/D50681
llvm-svn: 342044