Revised to use MemoryBuffer. Removed redundant llvm:: qualifiers.  Removed unnecessary c_str() calls.  Reformatted with clang-format.

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@178104 91177308-0d34-0410-b5e6-96231b3b80d8