Convert CowOperationType into strongly typed enums

Test: th
Bug: 304602386
Change-Id: I9856833331338266b7f6e1172f511319f3e39adc
diff --git a/common/cow_operation_convert.h b/common/cow_operation_convert.h
index a260a4a..5e29fc2 100644
--- a/common/cow_operation_convert.h
+++ b/common/cow_operation_convert.h
@@ -26,8 +26,8 @@
 namespace chromeos_update_engine {
 struct CowOperation {
   enum Type {
-    CowCopy = android::snapshot::kCowCopyOp,
-    CowReplace = android::snapshot::kCowReplaceOp,
+    CowCopy = static_cast<int>(android::snapshot::kCowCopyOp),
+    CowReplace = static_cast<int>(android::snapshot::kCowReplaceOp),
   };
   Type op{};
   uint64_t src_block{};