ScopedPrinterInfoSetter on crash prone blocks.

chrome/service/cloud_print/print_system_cups.cc

Index: chrome/service/cloud_print/print_system_cups.cc
diff --git a/chrome/service/cloud_print/print_system_cups.cc b/chrome/service/cloud_print/print_system_cups.cc
index e7fe1f8a3de7b558319ddfe252a1bea18a3bd931..280956159f708035c7c2ebc6f5c390852f6bd5c2 100644
--- a/chrome/service/cloud_print/print_system_cups.cc
+++ b/chrome/service/cloud_print/print_system_cups.cc
@@ -240,8 +240,8 @@ class PrinterWatcherCUPS
   PrinterWatcherCUPS(PrintSystemCUPS* print_system,
                      const std::string& printer_name)
       : printer_name_(printer_name),
-    delegate_(NULL),
-    print_system_(print_system) {
+      delegate_(NULL),
+      print_system_(print_system) {
   }
 
   ~PrinterWatcherCUPS() {
@@ -251,6 +251,10 @@ class PrinterWatcherCUPS
   // PrintSystem::PrinterWatcher implementation.
   virtual bool StartWatching(
       PrintSystem::PrinterWatcher::Delegate* delegate) OVERRIDE{
+    scoped_refptr<printing::PrintBackend> print_backend(
+        printing::PrintBackend::CreateInstance(NULL));
+    child_process_logging::ScopedPrinterInfoSetter prn_info(
+        print_backend->GetPrinterDriverInfo(printer_name));
     if (delegate_ != NULL)
       StopWatching();
     delegate_ = delegate;
@@ -279,42 +283,6 @@ class PrinterWatcherCUPS
     return print_system_->GetPrinterInfo(printer_name_, printer_info);
   }
 
-  void JobStatusUpdate() {
-    if (delegate_ == NULL)
-      return;  // Orphan call. We have been stopped already.
-    // For CUPS proxy, we are going to fire OnJobChanged notification
-    // periodically. Higher level will check if there are any outstanding
-    // jobs for this printer and check their status. If printer has no
-    // outstanding jobs, OnJobChanged() will do nothing.
-    delegate_->OnJobChanged();
-    MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&PrinterWatcherCUPS::JobStatusUpdate, this),
-        base::TimeDelta::FromSeconds(kJobUpdateTimeoutSeconds));
-  }
-
-  void PrinterUpdate() {
-    if (delegate_ == NULL)
-      return;  // Orphan call. We have been stopped already.
-    VLOG(1) << "CP_CUPS: Checking for printer updates: " << printer_name_;
-    if (print_system_->NotifyDelete() &&
-        !print_system_->IsValidPrinter(printer_name_)) {
-      delegate_->OnPrinterDeleted();
-      VLOG(1) << "CP_CUPS: Printer deleted: " << printer_name_;
-    } else {
-      std::string new_hash = GetSettingsHash();
-      if (settings_hash_ != new_hash) {
-        settings_hash_ = new_hash;
-        delegate_->OnPrinterChanged();
-        VLOG(1) << "CP_CUPS: Printer update detected for: " << printer_name_;
-      }
-    }
-    MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&PrinterWatcherCUPS::PrinterUpdate, this),
-        print_system_->GetUpdateTimeout());
-  }
-
  private:
   std::string GetSettingsHash() {
     printing::PrinterBasicInfo info;
@@ -340,7 +308,6 @@ class PrinterWatcherCUPS
 
     return base::MD5String(to_hash);
   }
-
   std::string printer_name_;
   PrintSystem::PrinterWatcher::Delegate* delegate_;
   scoped_refptr<PrintSystemCUPS> print_system_;
@@ -512,8 +479,9 @@ bool PrintSystemCUPS::ValidatePrintTicket(const std::string& printer_name,
 }
 
 // Print ticket on linux is a JSON string containing only one dictionary.
-bool PrintSystemCUPS::ParsePrintTicket(const std::string& print_ticket,
-                                  std::map<std::string, std::string>* options) {
+bool PrintSystemCUPS::ParsePrintTicket(
+    const std::string& print_ticket,
+    std::map<std::string, std::string>* options) {
   DCHECK(options);
   scoped_ptr<Value> ticket_value(base::JSONReader::Read(print_ticket, false));
   if (ticket_value == NULL || !ticket_value->IsType(Value::TYPE_DICTIONARY))
@@ -552,6 +520,7 @@ bool PrintSystemCUPS::GetPrinterCapsAndDefaults(
   }
 
   // TODO(gene): Retry multiple times in case of error.
+  child_process_logging::ScopedPrinterInfoSetter prn_info(server_info->backend->GetPrinterDriverInfo());
   if (!server_info->backend->GetPrinterCapsAndDefaults(short_printer_name,
                                                        printer_info) ) {
     return false;
@@ -573,6 +542,8 @@ bool PrintSystemCUPS::GetJobDetails(const std::string& printer_name,
   if (!server_info)
     return false;
 
+  child_process_logging::ScopedPrinterInfoSetter prn_info(
+      server_info->backend->GetPrinterDriverInfo());
   cups_job_t* jobs = NULL;
   int num_jobs = GetJobs(&jobs, server_info->url,
                          short_printer_name.c_str(), 1, -1);
@@ -738,6 +709,9 @@ PlatformJobId PrintSystemCUPS::SpoolPrintJob(
   if (!server_info)
     return false;
 
+  child_process_logging::ScopedPrinterInfoSetter prn_info(
+      server_info->backend->GetPrinterDriverInfo(printer_name));
+
   // We need to store options as char* string for the duration of the
   // cupsPrintFile2 call. We'll use map here to store options, since
   // Dictionary value from JSON parser returns wchat_t.