Merge branch '5.2' into 5.3

* 5.2:
  [5.2] Add missing `@return` annotations
  [4.4] Add missing `@return` annotations
  Handle lock with long key
  #42227 update phpdoc to recommend createIndex over ensureIndex

Author: nicolas-grekas

Data/Util/ArrayAccessibleResourceBundle.php

@@ -44,16 +44,25 @@ public function offsetExists($offset): bool
         return null !== $this->bundleImpl->get($offset);
     }
 
+    /**
+     * @return mixed
+     */
     public function offsetGet($offset)
     {
         return $this->get($offset);
     }
 
+    /**
+     * @return void
+     */
     public function offsetSet($offset, $value)
     {
         throw new BadMethodCallException('Resource bundles cannot be modified.');
     }
 
+    /**
+     * @return void
+     */
     public function offsetUnset($offset)
     {
         throw new BadMethodCallException('Resource bundles cannot be modified.');

Data/Util/RingBuffer.php

@@ -49,6 +49,8 @@ public function offsetExists($key): bool
 
     /**
      * {@inheritdoc}
+     *
+     * @return mixed
      */
     public function offsetGet($key)
     {
@@ -61,6 +63,8 @@ public function offsetGet($key)
 
     /**
      * {@inheritdoc}
+     *
+     * @return void
      */
     public function offsetSet($key, $value)
     {
@@ -76,6 +80,8 @@ public function offsetSet($key, $value)
 
     /**
      * {@inheritdoc}
+     *
+     * @return void
      */
     public function offsetUnset($key)
     {