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

llvm-svn: 344140

1 files changed, 5 insertions, 5 deletions

diff --git a/clang/unittests/AST/ASTImporterTest.cpp b/clang/unittests/AST/ASTImporterTest.cpp
index 366ff7f0e08..ecfdeb08661 100644
--- a/clang/unittests/AST/ASTImporterTest.cpp
+++ b/clang/unittests/AST/ASTImporterTest.cpp
@@ -37,10 +37,10 @@ createVirtualFileIfNeeded(ASTUnit *ToAST, StringRef FileName,
                           std::unique_ptr<llvm::MemoryBuffer> &&Buffer) {
   assert(ToAST);
   ASTContext &ToCtx = ToAST->getASTContext();
-  auto *OFS = static_cast<vfs::OverlayFileSystem *>(
+  auto *OFS = static_cast<llvm::vfs::OverlayFileSystem *>(
       ToCtx.getSourceManager().getFileManager().getVirtualFileSystem().get());
-  auto *MFS =
-      static_cast<vfs::InMemoryFileSystem *>(OFS->overlays_begin()->get());
+  auto *MFS = static_cast<llvm::vfs::InMemoryFileSystem *>(
+      OFS->overlays_begin()->get());
   MFS->addFile(FileName, 0, std::move(Buffer));
 }
 
@@ -2482,7 +2482,7 @@ TEST_P(ImportFriendFunctions, ImportFriendChangesLookup) {
   LookupRes = ToTU->noload_lookup(ToName);
   EXPECT_EQ(LookupRes.size(), 1u);
   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 1u);
-  
+
   auto *ToFriendF = cast<FunctionDecl>(Import(FromFriendF, Lang_CXX));
   LookupRes = ToTU->noload_lookup(ToName);
   EXPECT_EQ(LookupRes.size(), 1u);
@@ -2758,7 +2758,7 @@ TEST_P(ASTImporterTestBase, ImportOfEquivalentRecord) {
 
     ToR2 = Import(FromR, Lang_CXX);
   }
-  
+
   EXPECT_EQ(ToR1, ToR2);
 }