Hookup the PpdProvider in the printer setup flow.

chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.h

Index: chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.h
diff --git a/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.h b/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.h
index b959644da24312905d2c88e1580972f2667b67bd..2393fa3e839ba07826c59ad114a1c6cfe514385a 100644
--- a/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.h
+++ b/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.h
@@ -88,6 +88,18 @@ class CupsPrintersHandler : public ::settings::SettingsPageUIHandler,
   void OnPrintersFound(const std::vector<Printer>& printers) override;
   void OnDiscoveryDone() override;
 
+  // Invokes debugd to add the printer to CUPS.  If |ipp_everywhere| is true,
+  // automatic configuration will be attempted.  |ppd_path| should be a path

[Carlson, 2016/12/01 22:59:52]

Comment should indicate that ppd_path is ignored (or should be empty) if
ipp_everywhere is true.

[skau, 2016/12/05 20:40:51]

Done.

+  // to the ppd cache appropriate for the printer.
+  void AddPrinterToCups(std::unique_ptr<Printer> printer,
+                        const std::string& ppd_path,

[Carlson, 2016/12/05 23:40:11]

Shouldn't this be a base::FilePath?

[skau, 2016/12/06 20:55:46]

It goes onto the DBus as a string so it doesn't really matter.  But FilePath is
safer.  I've changed it.

+                        bool ipp_everywhere);
+
+  // Callback for PpdProvider::ResolveCallback.
+  void OnPPDResolved(std::unique_ptr<Printer> printer,
+                     printing::PpdProvider::CallbackResultCode result,
+                     base::FilePath ppd_path);
+
   std::unique_ptr<chromeos::PrinterDiscoverer> printer_discoverer_;
   std::unique_ptr<chromeos::printing::PpdProvider> ppd_provider_;