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

test/webkit/fast/regex/parentheses.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 // 1.  Redistributions of source code must retain the above copyright
 //     notice, this list of conditions and the following disclaimer.
 // 2.  Redistributions in binary form must reproduce the above copyright
 //     notice, this list of conditions and the following disclaimer in the
@@ skipping 256 matching lines @@
 var regexp56 = /(|a)/;
 shouldBe("regexp56.exec('a')", "['','']");
 var regexp57 = /(a|)/;
 shouldBe("regexp57.exec('a')", "['a','a']");
 
 // Tests that non-greedy repeat quantified parentheses will backtrack through multiple frames of subpattern matches.
 var regexp58 = /a|b(?:[^b])*?c/;
 shouldBe("regexp58.exec('badbc')", "['a']");
 var regexp59 = /(X(?:.(?!X))*?Y)|(Y(?:.(?!Y))*?Z)/g;
 shouldBe("'Y aaa X Match1 Y aaa Y Match2 Z'.match(regexp59)", "['X Match1 Y','Y Match2 Z']");
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