Add return types to internal & magic methods when possible

Author: nicolas-grekas

Data/Util/ArrayAccessibleResourceBundle.php

@@ -39,7 +39,7 @@ public function get($offset)
         return $value instanceof \ResourceBundle ? new static($value) : $value;
     }
 
-    public function offsetExists($offset)
+    public function offsetExists($offset): bool
     {
         return null !== $this->bundleImpl->get($offset);
     }
@@ -59,12 +59,12 @@ public function offsetUnset($offset)
         throw new BadMethodCallException('Resource bundles cannot be modified.');
     }
 
-    public function getIterator()
+    public function getIterator(): \Traversable
     {
         return $this->bundleImpl;
     }
 
-    public function count()
+    public function count(): int
     {
         return $this->bundleImpl->count();
     }

Data/Util/RingBuffer.php

@@ -42,7 +42,7 @@ public function __construct(int $size)
     /**
      * {@inheritdoc}
      */
-    public function offsetExists($key)
+    public function offsetExists($key): bool
     {
         return isset($this->indices[$key]);
     }