Issue 4127 - [emscripten] Convert subscription classes to C++ - Part 1

compiled/subscription/UserDefinedSubscription.cpp

+#include "UserDefinedSubscription.h"
+
+int UserDefinedSubscription::filterTypeToDefaults[] = {
+  UserDefinedSubscription::Defaults::BLOCKING,   // UNKNOWN
+  UserDefinedSubscription::Defaults::BLOCKING,   // INVALID
+  UserDefinedSubscription::Defaults::BLOCKING,   // COMMENT
+  UserDefinedSubscription::Defaults::BLOCKING,   // BLOCKING
+  UserDefinedSubscription::Defaults::WHITELIST,  // WHITELIST
+  UserDefinedSubscription::Defaults::ELEMHIDE,   // ELEMHIDE
+  UserDefinedSubscription::Defaults::ELEMHIDE,   // ELEMHIDEEXCEPTION
+  UserDefinedSubscription::Defaults::ELEMHIDE,   // ELEMHIDEEMULATION
+};
+
+UserDefinedSubscription::UserDefinedSubscription(const String& id)
+    : Subscription(Type::USERDEFINED, id), mDefaults(0)
+{
+}
+
+bool UserDefinedSubscription::IsDefaultFor(const Filter* filter) const
+{
+  return mDefaults & filterTypeToDefaults[filter->mType];
+}
+
+void UserDefinedSubscription::MakeDefaultFor(const Filter* filter)
+{
+  mDefaults |= filterTypeToDefaults[filter->mType];
+}
+
+OwnedString UserDefinedSubscription::Serialize() const
+{
+  OwnedString result(Subscription::Serialize());
+  if (mDefaults)
+  {
+    result.append(u"defaults="_str);
+    if (mDefaults & Defaults::BLOCKING)
+      result.append(u" blocking"_str);
+    if (mDefaults & Defaults::WHITELIST)
+      result.append(u" whitelist"_str);
+    if (mDefaults & Defaults::ELEMHIDE)
+      result.append(u" elemhide"_str);
+    result.append(u'\n');
+  }
+  return result;
+}