Revert "type: fix undefined index in ds_names[$source] before empty check"

From the docs:
"No warning is generated if the variable does not exist. That means empty() is
essentially the concise equivalent to !isset($var) || $var == false."

This reverts commit f2a4593558b3a3ec696e9cc1de93fa898b9521bb.

Reported-By: Benoit Monin (https://github.com/pommi/CGP/commit/f2a4593)

1 files changed, 1 insertions, 1 deletions

diff --git a/type/GenericStacked.class.php b/type/GenericStacked.class.php
index 42a252a..3f249c7 100644
--- a/type/GenericStacked.class.php
+++ b/type/GenericStacked.class.php
@@ -49,7 +49,7 @@ class Type_GenericStacked extends Type_Default {
 
                 $c = 0;
                 foreach ($sources as $source) {
-                        $dsname = (isset($this->ds_names[$source]) && !empty($this->ds_names[$source])) ? $this->ds_names[$source] : $source;
+                        $dsname = empty($this->ds_names[$source]) ? $source : $this->ds_names[$source];
                         $color = is_array($this->colors) ? (isset($this->colors[$source])?$this->colors[$source]:$this->colors[$c++]) : $this->colors;
                         $rrdgraph[] = sprintf('"LINE1:area_%s#%s:%s"', crc32hex($source), $this->validate_color($color), $this->rrd_escape($dsname));
                         $rrdgraph[] = sprintf('"GPRINT:min_%s:MIN:%s Min,"', crc32hex($source), $this->rrd_format);