Optimize word breaker.

Runtime/ui/txt/word_separate.cs

 namespace Unity.UIWidgets.ui {
     struct WordSeparate {
-        internal enum characterType {
+        internal enum CharacterType {
             LetterLike,
             Symbol,
             WhiteSpace
         }
 
 
-        internal static characterType classifyChar(string text, int index) {
+        internal static CharacterType classifyChar(string text, int index) {
-        internal static characterType classifyChar(char ch) {
+        internal static CharacterType classifyChar(char ch) {
-                return characterType.WhiteSpace;
+                return CharacterType.WhiteSpace;
-                return characterType.LetterLike;
+                return CharacterType.LetterLike;
-            return characterType.Symbol;
+            return CharacterType.Symbol;
         }
     }
 }

Runtime/ui/txt/wordbreaker.cs

             }
 
             char c = this._text.charAt(this._current);
-            WordSeparate.characterType preType = WordSeparate.classifyChar(c);
             bool preBoundaryChar = isBoundaryChar(c);
             this._current++;
             if (preBoundaryChar) {
+            this._findBoundaryCharOrTypeChange();
+            
+            return this._current;
+        }
+
+        void _findBoundaryCharOrTypeChange() {
+            char c = this._text.charAt(this._current);
+            bool preType = char.IsWhiteSpace(c);
-                c = this._text.charAt(this._current);
+                c = this._text.charAt(this._current);
-                var currentType = WordSeparate.classifyChar(c);
-                if ((currentType == WordSeparate.characterType.WhiteSpace) 
-                    != (preType == WordSeparate.characterType.WhiteSpace)) {
+
+                bool currentType = char.IsWhiteSpace(c);
+                if (currentType != preType) {
-            return this._current;
         }
         
         void _detectEmailOrUrl() {
         }
 
         public static bool isBoundaryChar(char code) {
-            if (char.IsPunctuation(code)) {
-                return true;
-            }
-            if (code >= 0x4E00 && code <= 0x9FFF) { // cjk https://en.wikipedia.org/wiki/CJK_Unified_Ideographs
-                return true;
-            }
-
-            // https://social.msdn.microsoft.com/Forums/en-US/0d1888de-9745-4dd1-80fd-d3c29d3e381d/checking-for-japanese-characters-in-a-string?forum=vcmfcatl
-            if (code >= 0x3040 && code <= 0x30FF) { // Hiragana or Katakana
-                return true;
-            }
-
-            return false;
+            return char.IsPunctuation(code) || code >= 0x4E00 && code <= 0x9FFF || code >= 0x3040 && code <= 0x30FF;
         }
         
         void nextUntilCodePoint() {