Moved SimplifyDocumentTitle from printing/backend

printing/backend/print_backend.h

Index: printing/backend/print_backend.h
diff --git a/printing/backend/print_backend.h b/printing/backend/print_backend.h
index 1d058bfabb3bd59740fb7121e98ea41c9619f286..d698d1149d84b37391dfdb8a372fb8837e88699d 100644
--- a/printing/backend/print_backend.h
+++ b/printing/backend/print_backend.h
@@ -10,7 +10,6 @@
 #include <vector>
 
 #include "base/memory/ref_counted.h"
-#include "base/strings/string16.h"
 #include "printing/print_job_constants.h"
 #include "printing/printing_export.h"
 
@@ -98,9 +97,6 @@ class PRINTING_EXPORT PrintBackend
   // Returns true if printer_name points to a valid printer.
   virtual bool IsValidPrinter(const std::string& printer_name) = 0;
 
-  // Simplify title to resolve issue with some drivers.
-  static base::string16 SimplifyDocumentTitle(const base::string16& title);
-
   // Allocate a print backend. If |print_backend_settings| is NULL, default
   // settings will be used.
   // Return NULL if no print backend available.