[Fonts] Sort material icons (#76691)

* Update update_icons.dart

* Merge and simplify identifier rewrites

* Update update_icons.dart

* Update update_icons.dart

* Update update_icons.dart

* Add newline

* remove whitespace

* Copy instead of moving

* Fix typo

* Clean up code

Introduce fullFlutterId and fix a small dartdoc bug

* Update update_icons.dart

* Implement sorting

* Remove trailing spaces

* Revert "Remove trailing spaces"

This reverts commit c198a16067.

* Revert "Implement sorting"

This reverts commit 0fac8c1f1c.

* Revert "Revert "Implement sorting""

This reverts commit 0f8ec2381a.

* Revert "Revert "Remove trailing spaces""

This reverts commit c3ef865879.

* xx

* add braces

dev/tools/update_icons.dart

@@ -244,7 +244,9 @@ Map<String, String> stringToTokenPairMap(String codepointData) {
 }
 
 String regenerateIconsFile(String iconData, Map<String, String> tokenPairMap) {
-  final Iterable<_Icon> newIcons = tokenPairMap.entries.map((MapEntry<String, String> entry) => _Icon(entry));
+  final List<_Icon> newIcons = tokenPairMap.entries.map((MapEntry<String, String> entry) => _Icon(entry)).toList();
+  newIcons.sort((_Icon a, _Icon b) => a._compareTo(b));
+
   final StringBuffer buf = StringBuffer();
   bool generating = false;
 
@@ -388,6 +390,16 @@ class _Icon {
   @override
   String toString() => id;
 
+  /// Analogous to [String.compareTo]
+  int _compareTo(_Icon b) {
+    // Sort a regular icon before its variants.
+    if (shortId == b.shortId) {
+      return id.length - b.id.length;
+    } else {
+      return flutterId.compareTo(b.flutterId);
+    }
+  }
+
   String _replaceLast(String string, String toReplace) {
     return string.replaceAll(RegExp('$toReplace\$'), '');
   }