8310003: Improve logging when default truststore is inaccessible

Reviewed-by: mullan

Author: koushikthirupattur

src/java.base/share/classes/sun/security/ssl/TrustStoreManager.java

@@ -112,7 +112,7 @@ private TrustStoreDescriptor(String storeName, String storeType,
                 SSLLogger.fine(
                     "trustStore is: " + storeName + "\n" +
                     "trustStore type is: " + storeType + "\n" +
-                    "trustStore provider is: " + storeProvider + "\n" +
+                    "trustStore provider is: " + (storeProvider.isEmpty() ? "unspecified" : storeProvider) + "\n" +
                     "the last modified time is: " + (new Date(lastModified)));
             }
         }