Ensure that data doesn't leak between users on cros chrome crash.

chrome/browser/chromeos/cros/cryptohome_library.cc

Index: chrome/browser/chromeos/cros/cryptohome_library.cc
diff --git a/chrome/browser/chromeos/cros/cryptohome_library.cc b/chrome/browser/chromeos/cros/cryptohome_library.cc
index 4be406c1723e1320b9144cb95485471aaa4993eb..d74d4e0e7fb5a244adffc0eef28c7f77993542ad 100644
--- a/chrome/browser/chromeos/cros/cryptohome_library.cc
+++ b/chrome/browser/chromeos/cros/cryptohome_library.cc
@@ -23,4 +23,8 @@ bool CryptohomeLibrary::Mount(const std::string& user_email,
   return chromeos::CryptohomeMount(user_email.c_str(), passhash.c_str());
 }
 
+bool CryptohomeLibrary::IsMounted() {
+  return chromeos::CryptohomeIsMounted();
+}
+
 }  // namespace chromeos