ChromeOS: fix crash in HashWallpaperFilesIdStr.

chromeos/cryptohome/system_salt_getter.cc

Index: chromeos/cryptohome/system_salt_getter.cc
diff --git a/chromeos/cryptohome/system_salt_getter.cc b/chromeos/cryptohome/system_salt_getter.cc
index 48f565e90a350f0fcaceeb5a01fab74edd9a85f1..bfe35961600d6374b5cf64d5604e2519f315dc26 100644
--- a/chromeos/cryptohome/system_salt_getter.cc
+++ b/chromeos/cryptohome/system_salt_getter.cc
@@ -42,6 +42,10 @@ void SystemSaltGetter::GetSystemSalt(
                  callback));
 }
 
+void SystemSaltGetter::AddOnSystemSaltReady(const base::Closure& closure) {
+  on_system_salt_ready_.push_back(closure);

[Darren Krahn, 2016/08/05 18:54:56]

Should the closure be called if salt is already available?

[Alexander Alekseev, 2016/08/06 05:00:12]

Done.

+}
+
 const SystemSaltGetter::RawSalt* SystemSaltGetter::GetRawSalt() const {
   return raw_salt_.empty() ? nullptr : &raw_salt_;
 }
@@ -74,6 +78,12 @@ void SystemSaltGetter::DidGetSystemSalt(
       system_salt.size() % 2 == 0U) {
       raw_salt_ = system_salt;
     system_salt_ = ConvertRawSaltToHexString(system_salt);
+
+    std::vector<base::Closure> callbacks;
+    callbacks.swap(on_system_salt_ready_);
+    for (const base::Closure& callback : callbacks) {
+      callback.Run();
+    }
   } else {
     LOG(WARNING) << "System salt not available";
   }