Update upb for php. (#2662)

php/ext/google/protobuf/def.c

@@ -209,14 +209,14 @@ static void init_generated_pool_once(TSRMLS_D) {
 
 static void descriptor_pool_init_c_instance(DescriptorPool *pool TSRMLS_DC) {
   zend_object_std_init(&pool->std, descriptor_pool_type TSRMLS_CC);
-  pool->symtab = upb_symtab_new(&pool->symtab);
+  pool->symtab = upb_symtab_new();
 
   ALLOC_HASHTABLE(pool->pending_list);
   zend_hash_init(pool->pending_list, 1, NULL, ZVAL_PTR_DTOR, 0);
 }
 
 static void descriptor_pool_free_c(DescriptorPool *pool TSRMLS_DC) {
-  upb_symtab_unref(pool->symtab, &pool->symtab);
+  upb_symtab_free(pool->symtab);
 
   zend_hash_destroy(pool->pending_list);
   FREE_HASHTABLE(pool->pending_list);

php/ext/google/protobuf/encode_decode.c

@@ -675,7 +675,7 @@ static void add_handlers_for_singular_field(upb_handlers *h,
     case UPB_TYPE_INT64:
     case UPB_TYPE_UINT64:
     case UPB_TYPE_DOUBLE:
-      upb_shim_set(h, f, offset, -1);
+      upb_msg_setscalarhandler(h, f, offset, -1);
       break;
     case UPB_TYPE_STRING:
     case UPB_TYPE_BYTES: {