Allow default case at the top of a switch scope in shaders

Revert "Removed translations of unused error message"

This reverts commit 6dbc75e.

Variable name change

Detecting multiple default cases in shaders

Removed translations of unused error message

Allowing default case at top of scope in switch statement in shaders

Author: Murrent

servers/rendering/shader_language.cpp

@@ -8460,9 +8460,11 @@ Error ShaderLanguage::_parse_block(BlockNode *p_block, const FunctionInfo &p_fun
 
 			pos = _get_tkpos();
 			tk = _get_token();
-			TokenType prev_type;
+			bool has_default = false;
 			if (tk.type == TK_CF_CASE || tk.type == TK_CF_DEFAULT) {
-				prev_type = tk.type;
+				if (tk.type == TK_CF_DEFAULT) {
+					has_default = true;
+				}
 				_set_tkpos(pos);
 			} else {
 				_set_expected_error("case", "default");
@@ -8476,17 +8478,15 @@ Error ShaderLanguage::_parse_block(BlockNode *p_block, const FunctionInfo &p_fun
 				}
 				pos = _get_tkpos();
 				tk = _get_token();
-				if (tk.type == TK_CF_CASE || tk.type == TK_CF_DEFAULT) {
-					if (prev_type == TK_CF_DEFAULT) {
-						if (tk.type == TK_CF_CASE) {
-							_set_error(RTR("Cases must be defined before default case."));
-							return ERR_PARSE_ERROR;
-						} else if (prev_type == TK_CF_DEFAULT) {
-							_set_error(RTR("Default case must be defined only once."));
-							return ERR_PARSE_ERROR;
-						}
+				if (tk.type == TK_CF_CASE) {
+					_set_tkpos(pos);
+					continue;
+				} else if (tk.type == TK_CF_DEFAULT) {
+					if (has_default) {
+						_set_error(RTR("Default case must be defined only once."));
+						return ERR_PARSE_ERROR;
 					}
-					prev_type = tk.type;
+					has_default = true;
 					_set_tkpos(pos);
 					continue;
 				} else {