Present the printer list from preferences for Chrome OS.

printing/backend/print_backend.h

 // Copyright (c) 2012 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 PRINTING_BACKEND_PRINT_BACKEND_H_
 #define PRINTING_BACKEND_PRINT_BACKEND_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 10 matching lines @@
 // This is the interface for platform-specific code for a print backend
 namespace printing {
 
 // Note: There are raw values. The |printer_name| and |printer_description|
 // require further interpretation on Mac. See existing callers for examples.
 struct PRINTING_EXPORT PrinterBasicInfo {
   PrinterBasicInfo();
   PrinterBasicInfo(const PrinterBasicInfo& other);
   ~PrinterBasicInfo();
 
+  std::string printer_id;

[Lei Zhang, 2016/10/28 21:55:51]

Is this field going to be ChromeOS only?

[skau, 2016/11/02 22:00:03]

I've added a guard for now.  It's probably useful in removing this nice bit of
code
https://cs.chromium.org/chromium/src/chrome/browser/ui/webui/print_preview/pr...
but I'm not 100% sure what it does so I don't want to migrate it right now.

[Lei Zhang, 2016/11/02 22:40:59]

Ok, so in patch set 2 you had [printer_id, printer_name, printer_description]
and in patch set 4 its now [printer_display_name, printer_name,
printer_description]. What was wrong with the way you had it in patch set 2?

[skau, 2016/11/02 23:38:16]

Sorry about the thrashing.  display_name is more consistent with how the field
is being used in the other platforms.  In patch set 2, I thought printer_name
was used to represent the display name rather than the name in CUPS.

   std::string printer_name;
   std::string printer_description;
   int printer_status;
   int is_default;
   std::map<std::string, std::string> options;
 };
 
 using PrinterList = std::vector<PrinterBasicInfo>;
 
 struct PRINTING_EXPORT PrinterSemanticCapsAndDefaults {
@@ skipping 88 matching lines @@
   static void SetNativeCupsEnabled(bool enabled);
 
  protected:
   friend class base::RefCountedThreadSafe<PrintBackend>;
   virtual ~PrintBackend();
 };
 
 }  // namespace printing
 
 #endif  // PRINTING_BACKEND_PRINT_BACKEND_H_