7121961: javadoc is missing a resource property

Reviewed-by: bpatel

src/share/classes/com/sun/tools/doclets/formats/html/resources/standard.properties

@@ -216,6 +216,7 @@ doclet.Groupname_already_used=In -group option, groupname already used: {0}
 doclet.Same_package_name_used=Package name format used twice: {0}
 doclet.Serialization.Excluded_Class=Non-transient field {1} uses excluded class {0}.
 doclet.Serialization.Nonexcluded_Class=Non-transient field {1} uses hidden, non-included class {0}.
+doclet.exception_encountered=Exception encountered while processing {1}\n{0}
 doclet.usage=Provided by Standard doclet:\n\
   -d <directory>                    Destination directory for output files\n\
   -use                              Create class and package usage pages\n\