Add dependencies locally

deps/protobuf/php/tests/force_c_ext.php

@@ -0,0 +1,14 @@
+<?php
+
+// We have to test this because the command-line argument will fail silently
+// if the extension could not be loaded:
+//    php -dextension=ext/google/protobuf/modules/protouf.so
+if (!extension_loaded("protobuf")) {
+    throw new Exception("Protobuf extension not loaded");
+}
+
+spl_autoload_register(function($class) {
+    if (strpos($class, "Google\\Protobuf") === 0) {
+        throw new Exception("When using the C extension, we should not load runtime class: " . $class);
+    }
+}, true, true);