make get_cfg_var return false

The spec says this returns false on error.

hphp/idl/options.idl.json

@@ -125,7 +125,7 @@
                 "HasDocComment"
             ],
             "return": {
-                "type": "String",
+                "type": "Variant",
                 "desc": "Returns the current value of the PHP configuration variable specified by option, or FALSE if an error occurs."
             },
             "args": [

hphp/runtime/ext/ext_options.cpp

@@ -118,8 +118,8 @@ Array f_get_extension_funcs(CStrRef module_name) {
   throw NotSupportedException(__func__, "extensions are built differently");
 }
 
-String f_get_cfg_var(CStrRef option) {
-  throw NotSupportedException(__func__, "global configurations not used");
+Variant f_get_cfg_var(CStrRef option) {
+  return false;
 }
 
 String f_get_current_user() {

hphp/runtime/ext/ext_options.h

@@ -30,7 +30,7 @@ int64_t f_dl(CStrRef library);
 bool f_extension_loaded(CStrRef name);
 Array f_get_loaded_extensions(bool zend_extensions = false);
 Array f_get_extension_funcs(CStrRef module_name);
-String f_get_cfg_var(CStrRef option);
+Variant f_get_cfg_var(CStrRef option);
 String f_get_current_user();
 Array f_get_defined_constants(CVarRef categorize = null_variant);
 String f_get_include_path();

hphp/system/class_map.cpp

@@ -11303,8 +11303,8 @@ const char *g_class_map[] = {
   NULL,
   NULL,
   (const char *)0x10006040, "get_cfg_var", "", (const char*)0, (const char*)0,
-  "/**\n * ( excerpt from http://php.net/manual/en/function.get-cfg-var.php )\n *\n * Gets the value of a PHP configuration option.\n *\n * This function will not return configuration information set when the\n * PHP was compiled, or read from an Apache configuration file.\n *\n * To check whether the system is using a configuration file, try\n * retrieving the value of the cfg_file_path configuration setting. If this\n * is available, a configuration file is being used.\n *\n * @option     string  The configuration option name.\n *\n * @return     string  Returns the current value of the PHP configuration\n *                     variable specified by option, or FALSE if an error\n *                     occurs.\n */",
-  (const char *)0x14 /* KindOfString */, (const char *)0x2000, "option", "", (const char *)0x14 /* KindOfString */, "", (const char *)0, "", (const char *)0, NULL,
+  "/**\n * ( excerpt from http://php.net/manual/en/function.get-cfg-var.php )\n *\n * Gets the value of a PHP configuration option.\n *\n * This function will not return configuration information set when the\n * PHP was compiled, or read from an Apache configuration file.\n *\n * To check whether the system is using a configuration file, try\n * retrieving the value of the cfg_file_path configuration setting. If this\n * is available, a configuration file is being used.\n *\n * @option     string  The configuration option name.\n *\n * @return     mixed   Returns the current value of the PHP configuration\n *                     variable specified by option, or FALSE if an error\n *                     occurs.\n */",
+  (const char *)0xffffffff /* KindOfUnknown: $t: Variant */, (const char *)0x2000, "option", "", (const char *)0x14 /* KindOfString */, "", (const char *)0, "", (const char *)0, NULL,
   NULL,
   NULL,
   NULL,

hphp/test/test_ext_options.cpp

@@ -127,12 +127,8 @@ bool TestExtOptions::test_get_extension_funcs() {
 }
 
 bool TestExtOptions::test_get_cfg_var() {
-  try {
-    f_get_cfg_var("");
-  } catch (const NotSupportedException& e) {
-    return Count(true);
-  }
-  return Count(false);
+  VERIFY(!f_get_cfg_var(""))
+  return Count(true);
 }
 
 bool TestExtOptions::test_get_current_user() {