third_party/protobuf: Update to HEAD (83d681ee2c)

third_party/protobuf/js/binary/encoder.js

 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 Google Inc.  All rights reserved.
 // https://developers.google.com/protocol-buffers/
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
@@ skipping 391 matching lines @@
 
 
 /**
  * Writes a UTF16 Javascript string to the buffer encoded as UTF8.
  * TODO(aappleby): Add support for surrogate pairs, reject unpaired surrogates.
  * @param {string} value The string to write.
  * @return {number} The number of bytes used to encode the string.
  */
 jspb.BinaryEncoder.prototype.writeString = function(value) {
   var oldLength = this.buffer_.length;
+ 
+  for (var i = 0; i < value.length; i++) {
+    
+    var c = value.charCodeAt(i);
 
-  // UTF16 to UTF8 conversion loop swiped from goog.crypt.stringToUtf8ByteArray.
-  for (var i = 0; i < value.length; i++) {
-    var c = value.charCodeAt(i);
     if (c < 128) {
       this.buffer_.push(c);
     } else if (c < 2048) {
       this.buffer_.push((c >> 6) | 192);
       this.buffer_.push((c & 63) | 128);
-    } else {
-      this.buffer_.push((c >> 12) | 224);
-      this.buffer_.push(((c >> 6) & 63) | 128);
-      this.buffer_.push((c & 63) | 128);
+    } else if (c < 65536) {
+      // Look for surrogates
+      if (c >= 0xD800 && c <= 0xDBFF && i + 1 < value.length) {
+        var second = value.charCodeAt(i + 1);
+        if (second >= 0xDC00 && second <= 0xDFFF) { // low surrogate
+          // http://mathiasbynens.be/notes/javascript-encoding#surrogate-formulae
+          c = (c - 0xD800) * 0x400 + second - 0xDC00 + 0x10000;
+
+          this.buffer_.push((c >> 18) | 240);
+          this.buffer_.push(((c >> 12) & 63 ) | 128);
+          this.buffer_.push(((c >> 6) & 63) | 128);
+          this.buffer_.push((c & 63) | 128);
+          i++;
+        }
+      }
+      else {
+        this.buffer_.push((c >> 12) | 224);
+        this.buffer_.push(((c >> 6) & 63) | 128);
+        this.buffer_.push((c & 63) | 128);
+      }
     }
   }
 
   var length = this.buffer_.length - oldLength;
   return length;
 };