Give PEImage a virtual destructor

sandbox/win/src/sandbox_nt_util.cc

Index: sandbox/win/src/sandbox_nt_util.cc
diff --git a/sandbox/win/src/sandbox_nt_util.cc b/sandbox/win/src/sandbox_nt_util.cc
index 28ddd47bff43262a9043d163e575c194909d1870..12dd7d8c88c72b561b6ba814b789e3d217ded5c1 100644
--- a/sandbox/win/src/sandbox_nt_util.cc
+++ b/sandbox/win/src/sandbox_nt_util.cc
@@ -361,6 +361,9 @@ UNICODE_STRING* AnsiToUnicode(const char* string) {
 }
 
 UNICODE_STRING* GetImageInfoFromModule(HMODULE module, uint32* flags) {
+  // PEImage's dtor won't be run during SEH unwinding, but that's OK.
+#pragma warning(push)
+#pragma warning(disable: 4509)
   UNICODE_STRING* out_name = NULL;
   __try {
     do {
@@ -389,6 +392,7 @@ UNICODE_STRING* GetImageInfoFromModule(HMODULE module, uint32* flags) {
   }
 
   return out_name;
+#pragma warning(pop)
 }
 
 UNICODE_STRING* GetBackingFilePath(PVOID address) {