fix wrapping of line in CHANGES.txt

Author: perezd

CHANGES.txt

@@ -22,7 +22,8 @@ Unreleased Changes (C++/Java/Python/PHP/Objective-C/C#/Ruby/JavaScript)
     on an error path.
   * Avoid expensive inlined code space for encoding message length for messages
     >= 128 bytes and instead do a procedure call to a shared out-of-line routine.
-  * util::DefaultFieldComparator will be final in a future version of protobuf. Subclasses should inherit from SimpleFieldComparator instead.
+  * util::DefaultFieldComparator will be final in a future version of protobuf.
+    Subclasses should inherit from SimpleFieldComparator instead.
 
   Java:
   * Detect invalid overflow of byteLimit and return InvalidProtocolBufferException as documented.