Add test on dart2js static analysis of method type parameters.

tests/language/language.status

Index: tests/language/language.status
diff --git a/tests/language/language.status b/tests/language/language.status
index d53cf790f90fcc89be0f690622b59ff74ab4ef36..bc19c4266a23e357783e15f10a4a4121f29d4989 100644
--- a/tests/language/language.status
+++ b/tests/language/language.status
@@ -49,6 +49,7 @@ generic_methods_test: CompiletimeError # Issue 25869
 generic_functions_test: CompiletimeError # Issue 25869
 generic_local_functions_test: CompiletimeError # Issue 25869
 generic_sends_test: CompiletimeError # Issue 25869
+generic_method_type_usage_test: CompiletimeError # Tests --generic-method-syntax, plus issue 25869
 
 [ ($compiler == none || $compiler == precompiler || $compiler == dart2app) && ($runtime == vm || $runtime == dart_precompiled || $runtime == dart_product) ]
 
@@ -94,6 +95,7 @@ generic_methods_test: RuntimeError # Issue 25869
 generic_functions_test: RuntimeError # Issue 25869
 generic_local_functions_test: RuntimeError # Issue 25869
 generic_sends_test: RuntimeError # Issue 25869
+generic_method_type_usage_test: CompiletimeError # Tests --generic-method-syntax, plus issue 25869
 config_import_test: Skip  # Issue 26250
 
 [ $compiler == none && $runtime == dartium && $system == linux && $arch != x64 ]