Track printer installations for each configuration.

chromeos/printing/printer_configuration.cc

Index: chromeos/printing/printer_configuration.cc
diff --git a/chromeos/printing/printer_configuration.cc b/chromeos/printing/printer_configuration.cc
index 9b6f66328c93af86efccb2da3a47f6a19cb1f1e6..f6cf4b6d76fd5f5cb62ab79115e77367b4094b4b 100644
--- a/chromeos/printing/printer_configuration.cc
+++ b/chromeos/printing/printer_configuration.cc
@@ -10,11 +10,12 @@
 
 namespace chromeos {
 
-Printer::Printer() : source_(SRC_USER_PREFS) {
+Printer::Printer() : source_(SRC_USER_PREFS), last_updated_(0) {
   id_ = base::GenerateGUID();
 }
 
-Printer::Printer(const std::string& id) : id_(id), source_(SRC_USER_PREFS) {
+Printer::Printer(const std::string& id, int64_t last_updated)
+    : id_(id), source_(SRC_USER_PREFS), last_updated_(last_updated) {
   if (id_.empty())
     id_ = base::GenerateGUID();
 }