missing array key guard

Author: eli-darkly

src/LaunchDarkly/FeatureFlagsState.php

@@ -58,7 +58,7 @@ public function isValid()
      */
     public function getFlagValue($key)
     {
-        return $this->_flagValues[$key];
+        return isset($this->_flagValues[$key]) ? $this->_flagValues[$key] : null;
     }
 
     /**

tests/MockFeatureRequester.php

@@ -13,7 +13,7 @@ public function __construct($baseurl, $key, $options)
 
     public function getFeature($key)
     {
-        return self::$flags[$key];
+        return isset(self::$flags[$key]) ? self::$flags[$key] : null;
     }
 
     public function getSegment($key)