Modify PrinterSetupResult enum to constant style.

chrome/browser/chromeos/printing/printer_configurer.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_CHROMEOS_PRINTING_PRINTER_CONFIGURER_H_
 #define CHROME_BROWSER_CHROMEOS_PRINTING_PRINTER_CONFIGURER_H_
 
 #include <memory>
 
 #include "base/callback_forward.h"
 #include "chromeos/printing/printer_configuration.h"
 
 class Profile;
 
 namespace chromeos {
 
 enum PrinterSetupResult {
-  FATAL_ERROR,
-  SUCCESS,              // Printer set up successfully
-  PRINTER_UNREACHABLE,  // Could not reach printer
-  DBUS_ERROR,           // Could not contact debugd
+  kFatalError = 0,          // Setup failed in an unrecognized way
+  kSuccess = 1,             // Printer set up successfully
+  kPrinterUnreachable = 2,  // Could not reach printer
+  kDbusError = 3,           // Could not contact debugd
+  // Space left for additional errors

[Lei Zhang, 2017/05/25 22:53:03]

Can you explain why this is needed?

[skau, 2017/05/25 23:11:07]

I'm leaving space for non-PPD errors and thought it might be nice.  There's no
logic that depends on this right now.  Is there a significant downside?

[Lei Zhang, 2017/05/25 23:24:06]

OK, the CL description hinted that you are going to use these for something. I
noticed https://codereview.chromium.org/2911523002 now. I didn't see it before
so I wasn't sure where you were going with this.

 
   // PPD errors
-  PPD_TOO_LARGE,     // PPD exceeds size limit
-  INVALID_PPD,       // PPD rejected by cupstestppd
-  PPD_NOT_FOUND,     // Could not find PPD
-  PPD_UNRETRIEVABLE  // Could not download PPD
+  kPpdTooLarge = 10,       // PPD exceeds size limit
+  kInvalidPpd = 11,        // PPD rejected by cupstestppd
+  kPpdNotFound = 12,       // Could not find PPD
+  kPpdUnretrievable = 13,  // Could not download PPD
+  kMaxValue = kPpdUnretrievable
 };
 
 using PrinterSetupCallback = base::Callback<void(PrinterSetupResult)>;
 
 // Configures printers by retrieving PPDs and registering the printer with CUPS.
 // Class must be constructed and used on the UI thread.
 class PrinterConfigurer {
  public:
   static std::unique_ptr<PrinterConfigurer> Create(Profile* profile);
 
   PrinterConfigurer(const PrinterConfigurer&) = delete;
   PrinterConfigurer& operator=(const PrinterConfigurer&) = delete;
 
   virtual ~PrinterConfigurer() = default;
 
   // Set up |printer| retrieving the appropriate PPD and registering the printer
   // with CUPS.  |callback| is called with the result of the operation.  This
   // method must be called on the UI thread and will run |callback| on the
   // UI thread.
   virtual void SetUpPrinter(const Printer& printer,
                             const PrinterSetupCallback& callback) = 0;
 
  protected:
   PrinterConfigurer() = default;
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_PRINTING_PRINTER_CONFIGURER_H_