[FileSystem] Remove Exists() from FileSpec

This patch removes the Exists method from FileSpec and updates its uses
with calls to the FileSystem.

Differential revision: https://reviews.llvm.org/D53845

llvm-svn: 345854
diff --git a/lldb/source/Plugins/DynamicLoader/Darwin-Kernel/DynamicLoaderDarwinKernel.cpp b/lldb/source/Plugins/DynamicLoader/Darwin-Kernel/DynamicLoaderDarwinKernel.cpp
index 5542dbe..65bc051 100644
--- a/lldb/source/Plugins/DynamicLoader/Darwin-Kernel/DynamicLoaderDarwinKernel.cpp
+++ b/lldb/source/Plugins/DynamicLoader/Darwin-Kernel/DynamicLoaderDarwinKernel.cpp
@@ -784,7 +784,7 @@
       // to do anything useful. This will force a clal to
       if (IsKernel()) {
         if (Symbols::DownloadObjectAndSymbolFile(module_spec, true)) {
-          if (module_spec.GetFileSpec().Exists()) {
+          if (FileSystem::Instance().Exists(module_spec.GetFileSpec())) {
             m_module_sp.reset(new Module(module_spec.GetFileSpec(),
                                          target.GetArchitecture()));
             if (m_module_sp.get() &&