Lift VFS from clang to llvm (NFC)

This patch moves the virtual file system form clang to llvm so it can be
used by more projects.

Concretely the patch:
 - Moves VirtualFileSystem.{h|cpp} from clang/Basic to llvm/Support.
 - Moves the corresponding unit test from clang to llvm.
 - Moves the vfs namespace from clang::vfs to llvm::vfs.
 - Formats the lines affected by this change, mostly this is the result of
   the added llvm namespace.

RFC on the mailing list:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/126657.html

Differential revision: https://reviews.llvm.org/D52783

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@344140 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 4 deletions

diff --git a/clang-tidy/ClangTidy.cpp b/clang-tidy/ClangTidy.cpp
index 729371fb..9ab85b61 100644
--- a/clang-tidy/ClangTidy.cpp
+++ b/clang-tidy/ClangTidy.cpp
@@ -96,7 +96,7 @@ private:
 class ErrorReporter {
 public:
   ErrorReporter(ClangTidyContext &Context, bool ApplyFixes,
-                llvm::IntrusiveRefCntPtr<vfs::FileSystem> BaseFS)
+                llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> BaseFS)
       : Files(FileSystemOptions(), BaseFS), DiagOpts(new DiagnosticOptions()),
         DiagPrinter(new TextDiagnosticPrinter(llvm::outs(), &*DiagOpts)),
         Diags(IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs), &*DiagOpts,
@@ -503,7 +503,7 @@ getCheckOptions(const ClangTidyOptions &Options,
 void runClangTidy(clang::tidy::ClangTidyContext &Context,
                   const CompilationDatabase &Compilations,
                   ArrayRef<std::string> InputFiles,
-                  llvm::IntrusiveRefCntPtr<vfs::FileSystem> BaseFS,
+                  llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> BaseFS,
                   bool EnableCheckProfile, llvm::StringRef StoreCheckProfile) {
   ClangTool Tool(Compilations, InputFiles,
                  std::make_shared<PCHContainerOperations>(), BaseFS);
@@ -590,9 +590,9 @@ void runClangTidy(clang::tidy::ClangTidyContext &Context,
 
 void handleErrors(ClangTidyContext &Context, bool Fix,
                   unsigned &WarningsAsErrorsCount,
-                  llvm::IntrusiveRefCntPtr<vfs::FileSystem> BaseFS) {
+                  llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> BaseFS) {
   ErrorReporter Reporter(Context, Fix, BaseFS);
-  vfs::FileSystem &FileSystem =
+  llvm::vfs::FileSystem &FileSystem =
       *Reporter.getSourceManager().getFileManager().getVirtualFileSystem();
   auto InitialWorkingDir = FileSystem.getCurrentWorkingDirectory();
   if (!InitialWorkingDir)