Remove abstract from class members in dart libraries

sdk/lib/utf/utf16.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 
 /**
  * Decodes the UTF-16 bytes as an iterable. Thus, the consumer can only convert
  * as much of the input as needed. Determines the byte order from the BOM,
  * or uses big-endian as a default. This method always strips a leading BOM.
  * Set the [replacementCodepoint] to null to throw an ArgumentError
@@ skipping 286 matching lines @@
   void backup([int by = 1]) {
     utf16EncodedBytesIterator.backup(2 * by);
   }
 
   int get remaining => (utf16EncodedBytesIterator.remaining + 1) ~/ 2;
 
   void skip([int count = 1]) {
     utf16EncodedBytesIterator.skip(2 * count);
   }
 
-  abstract int decode();
+  int decode();
 }
 
 /**
  * Convert UTF-16BE encoded bytes to utf16 code units by grouping 1-2 bytes
  * to produce the code unit (0-(2^16)-1).
  */
 class Utf16beBytesToCodeUnitsDecoder extends Utf16BytesToCodeUnitsDecoder {
   Utf16beBytesToCodeUnitsDecoder(List<int> utf16EncodedBytes, [
       int offset = 0, int length, bool stripBom = true,
       int replacementCodepoint = UNICODE_REPLACEMENT_CHARACTER_CODEPOINT]) :
@@ skipping 25 matching lines @@
       skip();
     }
   }
 
   int decode() {
     int lo = utf16EncodedBytesIterator.next();
     int hi = utf16EncodedBytesIterator.next();
     return (hi << 8) + lo;
   }
 }