Change MemoryBuffer::getFile to take a Twine.

llvm-svn: 193429
diff --git a/llvm/unittests/Support/MemoryBufferTest.cpp b/llvm/unittests/Support/MemoryBufferTest.cpp
index aa7ff6f..2b8806c 100644
--- a/llvm/unittests/Support/MemoryBufferTest.cpp
+++ b/llvm/unittests/Support/MemoryBufferTest.cpp
@@ -79,7 +79,7 @@
   OF.close();
 
   OwningPtr<MemoryBuffer> MB;
-  error_code EC = MemoryBuffer::getFile(TestPath, MB);
+  error_code EC = MemoryBuffer::getFile(TestPath.c_str(), MB);
   ASSERT_FALSE(EC);
 
   const char *BufData = MB->getBufferStart();