Stop leaking file descriptors.

After the open+fstat optimization, files were already opened for FileManager::getBufferForFile() and we closed them after reading them.
The problem was that when -working-directory was passed, the code path that actually reuses & closes the already opened file descriptor
was not followed.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@127639 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed