Hookup the PpdProvider in the printer setup flow.

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

Index: chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.cc
diff --git a/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.cc b/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.cc
index d21d63b191fb282dd5da2d36fa616a3fd9db40e0..7704c0dcf0195933c4e7a2f1abcc2812a0712b80 100644
--- a/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.cc
+++ b/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.cc
@@ -208,7 +208,6 @@ void CupsPrintersHandler::HandleAddCupsPrinter(const base::ListValue* args) {
       printer_protocol + "://" + printer_address + "/" + printer_queue;
 
   std::unique_ptr<Printer> printer = base::MakeUnique<Printer>(printer_id);
-  printer_id = printer->id();
   printer->set_display_name(printer_name);
   printer->set_description(printer_description);
   printer->set_manufacturer(printer_manufacturer);
@@ -216,23 +215,20 @@ void CupsPrintersHandler::HandleAddCupsPrinter(const base::ListValue* args) {
   printer->set_uri(printer_uri);
   if (!printer_ppd_path.empty()) {
     printer->mutable_ppd_reference()->user_supplied_ppd_url = printer_ppd_path;
+    bool cached = ppd_provider_->CachePpd(printer->ppd_reference(),
+                                          base::FilePath(printer_ppd_path));
+    VLOG(1) << "PPD Cached: " << cached;
   } else if (!printer_manufacturer.empty() && !printer_model.empty()) {
     Printer::PpdReference* ppd = printer->mutable_ppd_reference();
     ppd->effective_manufacturer = printer_manufacturer;
     ppd->effective_model = printer_model;
   }
 
-  chromeos::DebugDaemonClient* client =
-      chromeos::DBusThreadManager::Get()->GetDebugDaemonClient();
-  client->CupsAddPrinter(
-      printer_id,                               // record id
-      printer_uri,                              // uri
-      printer_ppd_path,                         // ppd location
-      printer_ppd_path.empty() ? true : false,  // ipp everywhere
-      base::Bind(&CupsPrintersHandler::OnAddedPrinter,
-                 weak_factory_.GetWeakPtr(), base::Passed(std::move(printer))),
-      base::Bind(&CupsPrintersHandler::OnAddPrinterError,
-                 weak_factory_.GetWeakPtr()));
+  const Printer::PpdReference& ppd_reference = printer->ppd_reference();

[Carlson, 2016/12/01 01:58:44]

Add a comment about why you're doing this?  Someone, someday is going to say
"Hey this is sort of a pointless temporary", remove it, and write
printer->ppd_reference() in the Resolve() below and there will be much
puzzlement and gnashing of teeth.

(At first glance *I* thought this was a pretty pointless temporary.  And I was
just bitten by this same sort of bug 2 weeks ago...)

[skau, 2016/12/01 21:45:12]

I really wish this was a compiler warning.  I've added a comment but the wording
isn't great.

+  ppd_provider_->Resolve(
+      ppd_reference,
+      base::Bind(&CupsPrintersHandler::OnPPDResolved,
+                 weak_factory_.GetWeakPtr(), base::Passed(&printer)));
 }
 
 void CupsPrintersHandler::OnAddedPrinter(std::unique_ptr<Printer> printer,
@@ -391,5 +387,30 @@ void CupsPrintersHandler::OnDiscoveryDone() {
                          base::StringValue("on-printer-discovery-done"));
 }
 
+void CupsPrintersHandler::OnPPDResolved(
+    std::unique_ptr<Printer> printer,
+    printing::PpdProvider::CallbackResultCode result,
+    base::FilePath path) {
+  if (result != printing::PpdProvider::SUCCESS) {
+    // TODO(skau): Add appropriate failure modes crbug.com/670068.
+    OnAddPrinterError();
+    return;
+  }
+
+  bool ipp_everywhere = Printer::IsIppEverywhere(*printer);
+  std::string ppd_path = ipp_everywhere ? "" : path.value();

[Carlson, 2016/12/01 01:58:44]

Wait, what?  So if it's an ipp everywhere printer we go out and try to resolve
it and then if we do resolve it successfully, we ignore the result?  I don't
understand what you're doing here.

[skau, 2016/12/01 21:45:12]

What I'm doing here makes no sense.  I've moved the IPP Everywhere check to
before the resolve call since IPP Everwhere should be keyed by
effective_manufacturer and effective_model and doesn't require a Resolve call.

+  std::string printer_id = printer->id();
+  std::string printer_uri = printer->uri();
+
+  chromeos::DebugDaemonClient* client =
+      chromeos::DBusThreadManager::Get()->GetDebugDaemonClient();
+  client->CupsAddPrinter(
+      printer_id, printer_uri, ppd_path, ipp_everywhere,
+      base::Bind(&CupsPrintersHandler::OnAddedPrinter,
+                 weak_factory_.GetWeakPtr(), base::Passed(&printer)),
+      base::Bind(&CupsPrintersHandler::OnAddPrinterError,
+                 weak_factory_.GetWeakPtr()));
+}
+
 }  // namespace settings
 }  // namespace chromeos