Skip applied mutations in Facade::setOldestVersion

Facade.h

@@ -10,7 +10,8 @@ using String = std::basic_string<uint8_t>;
 
 struct Facade {
 
-  explicit Facade(int64_t version) : versioned{version} {}
+  explicit Facade(int64_t version)
+      : unversionedVersion(version), versioned{version} {}
 
   struct View {
 
@@ -132,6 +133,9 @@ struct Facade {
     for (auto iter = versioned.begin(version), end = versioned.end(version);
          iter != end; ++iter) {
       auto m = *iter;
+      if (m.version < unversionedVersion) {
+        continue;
+      }
       switch (m.type) {
       case weaselab::VersionedMap::Set:
         unversioned[String(m.param1, m.param1Len)] =
@@ -152,6 +156,7 @@ struct Facade {
       }
     }
 
+    unversionedVersion = version;
     versioned.setOldestVersion(version);
   }
 
@@ -190,6 +195,7 @@ struct Facade {
     }
   }
 
+  int64_t unversionedVersion;
   std::map<String, String> unversioned;
   weaselab::VersionedMap versioned;
 };