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, 12 insertions, 12 deletions

diff --git a/clang/unittests/Tooling/ToolingTest.cpp b/clang/unittests/Tooling/ToolingTest.cpp
index 0a5150a31b7..186463f80af 100644
--- a/clang/unittests/Tooling/ToolingTest.cpp
+++ b/clang/unittests/Tooling/ToolingTest.cpp
@@ -149,10 +149,10 @@ TEST(newFrontendActionFactory, CreatesFrontendActionFactoryFromFactoryType) {
 }
 
 TEST(ToolInvocation, TestMapVirtualFile) {
-  llvm::IntrusiveRefCntPtr<vfs::OverlayFileSystem> OverlayFileSystem(
-      new vfs::OverlayFileSystem(vfs::getRealFileSystem()));
-  llvm::IntrusiveRefCntPtr<vfs::InMemoryFileSystem> InMemoryFileSystem(
-      new vfs::InMemoryFileSystem);
+  llvm::IntrusiveRefCntPtr<llvm::vfs::OverlayFileSystem> OverlayFileSystem(
+      new llvm::vfs::OverlayFileSystem(llvm::vfs::getRealFileSystem()));
+  llvm::IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem> InMemoryFileSystem(
+      new llvm::vfs::InMemoryFileSystem);
   OverlayFileSystem->pushOverlay(InMemoryFileSystem);
   llvm::IntrusiveRefCntPtr<FileManager> Files(
       new FileManager(FileSystemOptions(), OverlayFileSystem));
@@ -175,10 +175,10 @@ TEST(ToolInvocation, TestVirtualModulesCompilation) {
   // mapped module.map is found on the include path. In the future, expand this
   // test to run a full modules enabled compilation, so we make sure we can
   // rerun modules compilations with a virtual file system.
-  llvm::IntrusiveRefCntPtr<vfs::OverlayFileSystem> OverlayFileSystem(
-      new vfs::OverlayFileSystem(vfs::getRealFileSystem()));
-  llvm::IntrusiveRefCntPtr<vfs::InMemoryFileSystem> InMemoryFileSystem(
-      new vfs::InMemoryFileSystem);
+  llvm::IntrusiveRefCntPtr<llvm::vfs::OverlayFileSystem> OverlayFileSystem(
+      new llvm::vfs::OverlayFileSystem(llvm::vfs::getRealFileSystem()));
+  llvm::IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem> InMemoryFileSystem(
+      new llvm::vfs::InMemoryFileSystem);
   OverlayFileSystem->pushOverlay(InMemoryFileSystem);
   llvm::IntrusiveRefCntPtr<FileManager> Files(
       new FileManager(FileSystemOptions(), OverlayFileSystem));
@@ -403,10 +403,10 @@ TEST(ClangToolTest, ArgumentAdjusters) {
 
 TEST(ClangToolTest, BaseVirtualFileSystemUsage) {
   FixedCompilationDatabase Compilations("/", std::vector<std::string>());
-  llvm::IntrusiveRefCntPtr<vfs::OverlayFileSystem> OverlayFileSystem(
-      new vfs::OverlayFileSystem(vfs::getRealFileSystem()));
-  llvm::IntrusiveRefCntPtr<vfs::InMemoryFileSystem> InMemoryFileSystem(
-      new vfs::InMemoryFileSystem);
+  llvm::IntrusiveRefCntPtr<llvm::vfs::OverlayFileSystem> OverlayFileSystem(
+      new llvm::vfs::OverlayFileSystem(llvm::vfs::getRealFileSystem()));
+  llvm::IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem> InMemoryFileSystem(
+      new llvm::vfs::InMemoryFileSystem);
   OverlayFileSystem->pushOverlay(InMemoryFileSystem);
 
   InMemoryFileSystem->addFile(