Make initializing formals visible in the initializer list

tests/language/language.status

Index: tests/language/language.status
diff --git a/tests/language/language.status b/tests/language/language.status
index 64c1c4acb68d2cb4914b1aa41cd46b33a100fcb2..378a3813c3c8545cc7a98bbbf550b8c8d0bc6540 100644
--- a/tests/language/language.status
+++ b/tests/language/language.status
@@ -53,12 +53,6 @@ generic_methods_new_test: CompiletimeError # Issue 25869
 generic_methods_function_type_test: CompiletimeError # Issue 25869
 generic_methods_type_expression_test: CompiletimeError # Issue 25869
 
-# Experimental feature: Use initializing formals in initializers and constructor body.
-initializing_formal_access_test: CompiletimeError # Issue 26656
-initializing_formal_capture_test: CompiletimeError # Issue 26656
-initializing_formal_final_test: CompiletimeError # Issue 26656
-initializing_formal_type_test: CompiletimeError # Issue 26656
-
 [ ($compiler == none || $compiler == precompiler || $compiler == dart2app || $compiler == dart2appjit) && ($runtime == vm || $runtime == dart_precompiled || $runtime == dart_app) ]
 
 class_keyword_test/02: MissingCompileTimeError # Issue 13627
@@ -108,12 +102,6 @@ generic_methods_new_test: RuntimeError # Issue 25869
 generic_methods_function_type_test: RuntimeError # Issue 25869
 generic_methods_type_expression_test: RuntimeError # Issue 25869
 
-# Experimental feature: Use initializing formals in initializers and constructor body.
-initializing_formal_access_test: RuntimeError # Issue 26656
-initializing_formal_capture_test: RuntimeError # Issue 26656
-initializing_formal_final_test: RuntimeError # Issue 26656
-initializing_formal_type_test: RuntimeError # Issue 26656
-
 config_import_test: Skip  # Issue 26250
 
 [ $compiler == none && $runtime == dartium && $system == linux && $arch != x64 ]