Fixed --print-source crash.

src/prettyprinter.cc

 // Copyright 2011 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 429 matching lines @@
       memcpy(new_output, output_, pos_);
       DeleteArray(output_);
       output_ = new_output;
       size_ = new_size;
     }
   }
 }
 
 
 void PrettyPrinter::PrintStatements(ZoneList<Statement*>* statements) {
+  if (statements == NULL) return;
   for (int i = 0; i < statements->length(); i++) {
     if (i != 0) Print(" ");
     Visit(statements->at(i));
   }
 }
 
 
 void PrettyPrinter::PrintLabels(ZoneStringList* labels) {
   if (labels != NULL) {
     for (int i = 0; i < labels->length(); i++) {
@@ skipping 940 matching lines @@
     AddAttribute("mode", Variable::Mode2String(decl->mode()));
   }
   Visit(decl->proxy());
   if (decl->fun() != NULL) Visit(decl->fun());
 }
 
 
 #endif  // DEBUG
 
 } }  // namespace v8::internal