Add type inference logic for map literals

pkg/front_end/test/fasta/strong.status

 # Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE.md file.
 
 # Status file for the strong_test.dart test suite. This is testing generating
 # Kernel ASTs directly, that is, code in pkg/fasta/lib/src/kernel/ with
 # strong-mode enabled.
 
 DeltaBlue: Fail
 accessors: Fail
@@ skipping 39 matching lines @@
 stringliteral: Fail
 super_rasta_copy: Fail
 top_level_accessors: Fail
 type_variable_as_super: Fail
 typedef: Fail
 uninitialized_fields: Fail
 unused_methods: Fail
 void-methods: Fail
 
 inference/constructors_too_many_positional_arguments: Fail
-inference/downward_inference_miscellaneous: Fail
 inference/downwards_inference_annotations: Fail
 inference/downwards_inference_async_await: Fail
 inference/downwards_inference_for_each: Fail
 inference/downwards_inference_initializing_formal_default_formal: Fail
 inference/downwards_inference_inside_top_level: Fail
 inference/downwards_inference_on_function_expressions: Fail
 inference/downwards_inference_on_function_of_t_using_the_t: Fail
 inference/downwards_inference_on_generic_function_expressions: Fail
 inference/downwards_inference_on_list_literals_infer_downwards: Fail
 inference/downwards_inference_on_list_literals_infer_if_value_types_match_context: Fail
 inference/downwards_inference_on_map_literals: Fail
-inference/downwards_inference_yield_yield_star: Fail
 inference/future_or_subtyping: Fail
 inference/future_then: Fail
 inference/future_then_2: Fail
 inference/future_then_3: Fail
 inference/future_then_4: Fail
 inference/future_then_5: Fail
 inference/future_then_6: Fail
 inference/future_then_conditional: Fail
 inference/future_then_conditional_2: Fail
 inference/future_then_conditional_3: Fail
@@ skipping 30 matching lines @@
 inference/infer_consts_transitively_2: Fail
 inference/infer_consts_transitively_2_a: Fail
 inference/infer_correctly_on_multiple_variables_declared_together: Fail
 inference/infer_from_complex_expressions_if_outer_most_value_is_precise: Fail
 inference/infer_from_rhs_only_if_it_wont_conflict_with_overridden_fields: Fail
 inference/infer_from_rhs_only_if_it_wont_conflict_with_overridden_fields2: Fail
 inference/infer_from_variables_in_cycle_libs_when_flag_is_on: Fail
 inference/infer_from_variables_in_cycle_libs_when_flag_is_on2: Fail
 inference/infer_from_variables_in_non_cycle_imports_with_flag: Fail
 inference/infer_from_variables_in_non_cycle_imports_with_flag2: Fail
-inference/infer_list_literal_nested_in_map_literal: Fail
 inference/infer_prefix_expression: Fail
 inference/infer_statics_transitively: Fail
 inference/infer_statics_transitively3: Fail
 inference/infer_statics_transitively_a: Fail
 inference/infer_statics_with_method_invocations: Fail
 inference/infer_type_on_var_from_field: Fail
-inference/infer_typed_map_literal: Fail
 inference/infer_types_on_generic_instantiations_in_library_cycle: Fail
 inference/infer_types_on_loop_indices_for_each_loop: Fail
 inference/infer_types_on_loop_indices_for_loop_with_inference: Fail
-inference/inferred_nonstatic_field_depends_on_static_field_complex: Fail
 inference/inferred_type_cascade: Fail
 inference/inferred_type_extract_method_tear_off: Fail
 inference/inferred_type_extract_method_tear_off_via_interface: Fail
-inference/inferred_type_is_typedef: Fail
 inference/inferred_type_is_typedef_parameterized: Fail
 inference/inferred_type_uses_synthetic_function_type_named_param: Fail
 inference/inferred_type_uses_synthetic_function_type_positional_param: Fail
-inference/inferred_type_via_closure_multiple_levels_of_nesting: Fail
 inference/lambda_does_not_have_propagated_type_hint: Fail
 inference/list_literals_can_infer_null_top_level: Fail
-inference/map_literals: Fail
-inference/map_literals_can_infer_null: Fail
 inference/map_literals_can_infer_null_top_level: Fail
-inference/map_literals_top_level: Fail
 inference/method_call_with_type_arguments_static_method: Fail
 inference/null_coalescing_operator: Fail
 inference/null_coalescing_operator_2: Fail
 inference/null_literal_should_not_infer_as_bottom: Fail
 inference/propagate_inference_to_field_in_class: Fail
 inference/reference_to_typedef: Fail
 inference/refine_binary_expression_type_type_parameter_t_double: Fail
 inference/refine_binary_expression_type_type_parameter_t_int: Fail
 inference/refine_binary_expression_type_type_parameter_t_t: Fail
 inference/unsafe_block_closure_inference_closure_call: Fail
 inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr1: Fail
 inference/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr1: Fail
 inference/unsafe_block_closure_inference_function_call_implicit_type_param_via_expr: Fail
 inference/unsafe_block_closure_inference_function_call_no_type_param_via_expr: Fail
-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/void_return_type_subtypes_dynamic: Fail
 
 rasta/abstract_constructor: Fail
 rasta/bad_constructor_redirection: Fail
 rasta/bad_continue: Fail
 rasta/bad_default_constructor: Fail
 rasta/bad_explicit_super_constructor: Fail
 rasta/bad_implicit_super_constructor: Fail
 rasta/bad_interpolation: Fail
 rasta/bad_redirection: Fail
@@ skipping 68 matching lines @@
 rasta/this_invoke: Fail
 rasta/try_label: Fail
 rasta/type_literals: VerificationError
 rasta/type_with_parse_error: Fail
 rasta/typedef: VerificationError
 rasta/unresolved: Fail
 rasta/unresolved_constructor: Fail
 rasta/unresolved_for_in: Fail
 rasta/unresolved_recovery: Fail
 rasta/unsupported_platform_library: Fail