DevTools: cleanup debugger tests.

LayoutTests/inspector/sources/debugger/open-close-open-expected.txt

 Tests that scripts panel displays resource content correctly after the open - close - open sequence. Bug 56747
 
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 Running: testSourceFrameContent
 ==Source frame contents start==
 
 
 
 
 <script>
 
 function test()
@@ skipping 13 matching lines @@
                         next();
                     }
                 }
             ]);
         }
     });
 }
 
 </script>
 ==Source frame contents end==
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