Make sure files end with exactly one new line and police this in presubmit.

test/mjsunit/debug-stepin-positions.js

 // Copyright 2008 the V8 project authors. All rights reserved.
 // 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.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 203 matching lines @@
 })(Object);
 TestCaseWithDebugger(fun);
 
 // Global function, global object construction, calls before pause point.
 var fun = (function(p) {
   return function() {
     var res = [ Math.abs(new Object()), DebuggerStatement(), Math./*#*/abs(4), /*#*/new Object()./*#*/toString() ]; /*positions*/
   };
 })(Object);
 TestCaseWithDebugger(fun);
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