Further tweaks to safe and lang injection 2, a=chris

diff --git a/src/models/PhraseModel.php b/src/models/PhraseModel.php
index fe039efd9..387143584 100755
--- a/src/models/PhraseModel.php
+++ b/src/models/PhraseModel.php
@@ -753,8 +753,8 @@ class PhraseModel extends ParallelModel
                     $weight = substr($matches[2][0], strlen($meta_word));
                 }
             }
-            if (!empty($matches[0]) && substr($matches[0], 0, 11)
-                == 'media:image') {
+            if (!empty($matches[0]) && is_string($matches[0])
+                && substr($matches[0], 0, 11) == 'media:image') {
                 $found_media_image = true;
             }
             if ($meta_word == 'safe:' && !empty($matches[0])) {
@@ -773,7 +773,7 @@ class PhraseModel extends ParallelModel
         }
         $found_metas = array_unique($found_metas);
         if (!$found_media_image &&
-            (!empty($found_metas) || !empty($phrase_string)) {
+            (!empty($found_metas) || !empty($phrase_string))) {
             if (!$found_lang) {
                 $lang_parts = explode("-", $locale_tag);
                 $found_metas[] = "lang:" . $lang_parts[0];
@@ -1554,7 +1554,7 @@ class PhraseModel extends ParallelModel
             $out_query = "";
             $pipe = "";
             foreach ($disjunct_phrases as $disjunct) {
-                if (!stristr($disjunct, "lang:")&&
+                if (!stristr($disjunct, "lang:") &&
                     !stristr($disjunct, "media:image")) {
                     $locale_tag = L\guessLocaleFromString($original_query);
                     $lang_parts = explode("-", $locale_tag);