Use decode() instead of decodeIfSupported()

Author: alcaeus

src/ChangeStream.php

@@ -114,7 +114,7 @@ public function current()
             return $value;
         }
 
-        return $this->codec->decodeIfSupported($value);
+        return $this->codec->decode($value);
     }
 
     /** @return CursorId */

src/Operation/FindAndModify.php

@@ -262,8 +262,7 @@ public function execute(Server $server)
             $result = current($cursor->toArray());
             assert($result instanceof Document);
 
-            $decoded = $this->options['codec']->decodeIfSupported($result->get('value'));
-            assert($decoded === null || is_object($decoded));
+            $decoded = $this->options['codec']->decode($result->get('value'));
 
             return $decoded;
         }