Improve Character emulation

Author: zbynek

dev/core/src/com/google/gwt/dev/js/rhino/TokenStream.java

@@ -1266,14 +1266,19 @@ else if (!RESERVED_KEYWORD_AS_IDENTIFIER)
                 int reEnd = stringBufferTop;
 
                 while (true) {
-                    if (in.match('g'))
+                    if (in.match('g')) {
                         addToString('g');
-                    else if (in.match('i'))
+                    } else if (in.match('i')) {
                         addToString('i');
-                    else if (in.match('m'))
+                    } else if (in.match('m')) {
                         addToString('m');
-                    else
+                    } else if (in.match('u')) {
+                        addToString('u');
+                    } else if (in.match('v')) {
+                        addToString('v');
+                    } else {
                         break;
+                    }
                 }
 
                 if (isAlpha(in.peek())) {

user/super/com/google/gwt/emul/java/lang/CaseMapper.java

@@ -23,7 +23,23 @@ public static char charToLowerCase(char c) {
   }
 
   public static char charToUpperCase(char c) {
-    return String.valueOf(c).toUpperCase().charAt(0);
+    String upper = String.valueOf(c).toUpperCase();
+    return hasExtraCodePoints(upper) ? c : upper.charAt(0);
+  }
+
+  public static int intToLowerCase(int codePoint) {
+    return String.NativeString.fromCodePoint(codePoint).toLowerCase().codePointAt(0);
+  }
+
+  public static int intToUpperCase(int codePoint) {
+    String upper = String.NativeString.fromCodePoint(codePoint).toUpperCase();
+    return hasExtraCodePoints(upper) ? codePoint : upper.codePointAt(0);
+  }
+
+  // If String.toUpperCase produces more than 1 codepoint, Character.toUpperCase should
+  // act either as identity or title-case conversion (not supported in GWT).
+  private static boolean hasExtraCodePoints(String str) {
+    return str.asNativeString().codePointAt(1) > 0;
   }
 
   private CaseMapper() {}