AST: remove ScalarTraits<size_t> on Windows

Because `size_t` is the same as `uint64_t` on Windows, this results in a
conflicting definition of the `ScalarTraits`.

Author: compnerd

include/swift/AST/ExperimentalDependencies.h

@@ -939,8 +939,9 @@ template <typename GraphT> class DotFileEmitter {
 // MARK: Declarations for YAMLTraits for reading/writing of SourceFileDepGraph
 //==============================================================================
 
-// This introduces a redefinition for Linux.
-#if !defined(__linux__)
+// This introduces a redefinition where ever std::is_same_t<size_t, uint64_t>
+// holds
+#if !(defined(__linux__) || defined(_WIN64))
 LLVM_YAML_DECLARE_SCALAR_TRAITS(size_t, QuotingType::None)
 #endif
 LLVM_YAML_DECLARE_ENUM_TRAITS(swift::experimental_dependencies::NodeKind)

lib/AST/ExperimentalDependencies.cpp

@@ -262,7 +262,7 @@ void SourceFileDepGraph::verifySame(const SourceFileDepGraph &other) const {
 namespace llvm {
 namespace yaml {
 // This introduces a redefinition for Linux.
-#if !defined(__linux__)
+#if !(defined(__linux__) || defined(_WIN64))
 void ScalarTraits<size_t>::output(const size_t &Val, void *, raw_ostream &out) {
   out << Val;
 }