Add subtype matching rules for function types.

pkg/front_end/test/fasta/strong.status

Index: pkg/front_end/test/fasta/strong.status
diff --git a/pkg/front_end/test/fasta/strong.status b/pkg/front_end/test/fasta/strong.status
index dfd1d442539c5acdc4bd159b6bda3e1c166a26ec..e33fcd921a5cb711f0b40dc221f6387dbdb27259 100644
--- a/pkg/front_end/test/fasta/strong.status
+++ b/pkg/front_end/test/fasta/strong.status
@@ -74,7 +74,6 @@ inference/block_bodied_lambdas_sync_star: Fail
 inference/circular_reference_via_closures: Fail
 inference/circular_reference_via_closures_initializer_types: Fail
 inference/constructors_infer_from_arguments: Fail
-inference/constructors_infer_from_arguments_argument_not_assignable: Fail
 inference/constructors_infer_from_arguments_const: Fail
 inference/constructors_infer_from_arguments_const_with_upper_bound: Fail
 inference/constructors_infer_from_arguments_factory: Fail
@@ -202,7 +201,6 @@ inference/refine_binary_expression_type_type_parameter_t_t: Fail
 inference/type_promotion_stopped_by_access_in_a_closure: Fail
 inference/type_promotion_stopped_by_mutation_in_a_closure: Fail
 inference/unsafe_block_closure_inference_closure_call: Fail
-inference/unsafe_block_closure_inference_constructor_call_implicit_type_param: Fail
 inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param: Fail
 inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr1: Fail
 inference/unsafe_block_closure_inference_function_call_explicit_type_param: Fail
@@ -214,7 +212,6 @@ inference/unsafe_block_closure_inference_function_call_no_type_param_via_expr: F
 inference/unsafe_block_closure_inference_in_map_dynamic: Fail
 inference/unsafe_block_closure_inference_in_map_typed: Fail
 inference/unsafe_block_closure_inference_in_map_untyped: Fail
-inference/unsafe_block_closure_inference_method_call_implicit_type_param: Fail
 inference/void_return_type_subtypes_dynamic: Fail
 
 rasta/abstract_constructor: Fail