win x86: Grab bag of restructuring to get tests working on x86-on-x86

snapshot/win/exception_snapshot_win.h

Index: snapshot/win/exception_snapshot_win.h
diff --git a/snapshot/win/exception_snapshot_win.h b/snapshot/win/exception_snapshot_win.h
index 588c4ac9f642452d54534bf6c1916a7022b5de8c..277cd4a5117eb23ddea04d1f6926245cb34441fa 100644
--- a/snapshot/win/exception_snapshot_win.h
+++ b/snapshot/win/exception_snapshot_win.h
@@ -61,6 +61,12 @@ class ExceptionSnapshotWin final : public ExceptionSnapshot {
   const std::vector<uint64_t>& Codes() const override;
 
  private:
+  template <class ExceptionRecordType, class ContextType>
+  bool InitializeFromExceptionPointers(
+      const ProcessReaderWin& process_reader,
+      const EXCEPTION_POINTERS& exception_pointers,
+      ContextType* context_record);
+
 #if defined(ARCH_CPU_X86_FAMILY)
   union {
     CPUContextX86 x86;