php 7.0 support

instead of using the void return type, add more ReturnTypeWillChange annotations

php/composer.json

@@ -6,7 +6,7 @@
   "homepage": "https://developers.google.com/protocol-buffers/",
   "license": "BSD-3-Clause",
   "require": {
-    "php": ">=7.1.0",
+    "php": ">=7.0.0",
     "ext-bcmath": "*"
   },
   "require-dev": {

php/src/Google/Protobuf/Internal/MapField.php

@@ -154,7 +154,8 @@ class MapField implements \ArrayAccess, \IteratorAggregate, \Countable
      * @throws \ErrorException Invalid type for value.
      * @throws \ErrorException Non-existing key.
      */
-    public function offsetSet($key, $value): void
+    #[\ReturnTypeWillChange]
+    public function offsetSet($key, $value)
     {
         $this->checkKey($this->key_type, $key);
 
@@ -212,7 +213,8 @@ class MapField implements \ArrayAccess, \IteratorAggregate, \Countable
      * @return void
      * @throws \ErrorException Invalid type for key.
      */
-    public function offsetUnset($key): void
+    #[\ReturnTypeWillChange]
+    public function offsetUnset($key)
     {
         $this->checkKey($this->key_type, $key);
         unset($this->container[$key]);

php/src/Google/Protobuf/Internal/MapFieldIter.php

@@ -68,7 +68,8 @@ class MapFieldIter implements \Iterator
      *
      * @return void
      */
-    public function rewind(): void
+    #[\ReturnTypeWillChange]
+    public function rewind()
     {
         reset($this->container);
     }
@@ -119,7 +120,8 @@ class MapFieldIter implements \Iterator
      *
      * @return void
      */
-    public function next(): void
+    #[\ReturnTypeWillChange]
+    public function next()
     {
         next($this->container);
     }

php/src/Google/Protobuf/Internal/RepeatedField.php

@@ -140,7 +140,8 @@ class RepeatedField implements \ArrayAccess, \IteratorAggregate, \Countable
      * @throws \ErrorException Non-existing index.
      * @throws \ErrorException Incorrect type of the element.
      */
-    public function offsetSet($offset, $value): void
+    #[\ReturnTypeWillChange]
+    public function offsetSet($offset, $value)
     {
         switch ($this->type) {
             case GPBType::SFIXED32:
@@ -211,7 +212,8 @@ class RepeatedField implements \ArrayAccess, \IteratorAggregate, \Countable
      * @throws \ErrorException The element to be removed is not at the end of the
      * RepeatedField.
      */
-    public function offsetUnset($offset): void
+    #[\ReturnTypeWillChange]
+    public function offsetUnset($offset)
     {
         $count = count($this->container);
         if (!is_numeric($offset) || $count === 0 || $offset !== $count - 1) {

php/src/Google/Protobuf/Internal/RepeatedFieldIter.php

@@ -71,7 +71,8 @@ class RepeatedFieldIter implements \Iterator
      *
      * @return void
      */
-    public function rewind(): void
+    #[\ReturnTypeWillChange]
+    public function rewind()
     {
         $this->position = 0;
     }
@@ -103,7 +104,8 @@ class RepeatedFieldIter implements \Iterator
      *
      * @return void
      */
-    public function next(): void
+    #[\ReturnTypeWillChange]
+    public function next()
     {
         ++$this->position;
     }