LibUnicode: Perform number system lookups by enumeration value

Now that number systems are generated as an enum, we can generated the
number system data in the order of that enum. This lets us perform
lookups of that data by index instead of a loop of string comparisons.

Meta/Lagom/Tools/CodeGenerators/LibUnicode/GenerateUnicodeNumberFormat.cpp

@@ -135,7 +135,7 @@ using NumericSymbolList = Vector<StringIndexType>;
 struct NumberSystem {
     unsigned hash() const
     {
-        auto hash = pair_int_hash(system, symbols);
+        auto hash = int_hash(symbols);
         hash = pair_int_hash(hash, primary_grouping_size);
         hash = pair_int_hash(hash, secondary_grouping_size);
         hash = pair_int_hash(hash, decimal_format);
@@ -152,8 +152,7 @@ struct NumberSystem {
 
     bool operator==(NumberSystem const& other) const
     {
-        return (system == other.system)
+        return (symbols == other.symbols)
-            && (symbols == other.symbols)
             && (primary_grouping_size == other.primary_grouping_size)
             && (secondary_grouping_size == other.secondary_grouping_size)
             && (decimal_format == other.decimal_format)
@@ -167,7 +166,6 @@ struct NumberSystem {
             && (scientific_format == other.scientific_format);
     }
 
-    StringIndexType system { 0 };
     NumericSymbolListIndexType symbols { 0 };
 
     u8 primary_grouping_size { 0 };
@@ -191,8 +189,7 @@ struct AK::Formatter<NumberSystem> : Formatter<FormatString> {
     ErrorOr<void> format(FormatBuilder& builder, NumberSystem const& system)
     {
         return Formatter<FormatString>::format(builder,
-            "{{ {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {} }}",
+            "{{ {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {} }}",
-            system.system,
             system.symbols,
             system.primary_grouping_size,
             system.secondary_grouping_size,
@@ -256,7 +253,7 @@ struct AK::Traits<Unit> : public GenericTraits<Unit> {
 };
 
 struct Locale {
-    HashMap<String, NumberSystemIndexType> number_systems;
+    Vector<NumberSystemIndexType> number_systems;
     HashMap<String, UnitIndexType> units {};
 };
 
@@ -459,13 +456,18 @@ static ErrorOr<void> parse_number_systems(String locale_numbers_path, UnicodeLoc
     auto const& locale_object = main_object.as_object().get(numbers_path.parent().basename());
     auto const& locale_numbers_object = locale_object.as_object().get("numbers"sv);
 
-    HashMap<String, NumberSystem> number_systems;
+    Vector<Optional<NumberSystem>> number_systems;
+    number_systems.resize(locale_data.number_systems.size());
 
     auto ensure_number_system = [&](auto const& system) -> NumberSystem& {
-        return number_systems.ensure(system, [&]() {
+        auto system_index = locale_data.number_systems.find_first_index(system).value();
-            auto system_index = locale_data.unique_strings.ensure(system);
+        VERIFY(system_index < number_systems.size());
-            return NumberSystem { .system = system_index };
+
-        });
+        auto& number_system = number_systems.at(system_index);
+        if (!number_system.has_value())
+            number_system = NumberSystem {};
+
+        return number_system.value();
     };
 
     auto parse_number_format = [&](auto const& format_object) {
@@ -593,9 +595,14 @@ static ErrorOr<void> parse_number_systems(String locale_numbers_path, UnicodeLoc
         }
     });
 
+    locale.number_systems.ensure_capacity(number_systems.size());
+
     for (auto& number_system : number_systems) {
-        auto system_index = locale_data.unique_systems.ensure(move(number_system.value));
+        NumberSystemIndexType system_index = 0;
-        locale.number_systems.set(number_system.key, system_index);
+        if (number_system.has_value())
+            system_index = locale_data.unique_systems.ensure(number_system.release_value());
+
+        locale.number_systems.append(system_index);
     }
 
     return {};
@@ -833,7 +840,6 @@ struct NumberFormatImpl {
 };
 
 struct NumberSystemData {
-    @string_index_type@ system { 0 };
     @numeric_symbol_list_index_type@ symbols { 0 };
 
     u8 primary_grouping_size { 0 };
@@ -920,17 +926,20 @@ static NumberSystemData const* find_number_system(StringView locale, StringView
     if (!locale_value.has_value())
         return nullptr;
 
+    auto number_system_value = number_system_from_string(system);
+    if (!number_system_value.has_value())
+        return nullptr;
+
     auto locale_index = to_underlying(*locale_value) - 1; // Subtract 1 because 0 == Locale::None.
+    auto number_system_index = to_underlying(*number_system_value);
+
     auto const& number_systems = s_locale_number_systems.at(locale_index);
+    number_system_index = number_systems.at(number_system_index);
 
-    for (auto system_index : number_systems) {
+    if (number_system_index == 0)
-        auto const& number_system = s_number_systems.at(system_index);
+        return nullptr;
 
-        if (system == s_string_list[number_system.system])
+    return &s_number_systems.at(number_system_index);
-            return &number_system;
-    };
-
-    return nullptr;
 }
 
 Optional<StringView> get_number_system_symbol(StringView locale, StringView system, NumericSymbol symbol)