support resolving .packages in FE

tests/standalone/standalone.status

 # Copyright (c) 2013, 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 file.
 
 # WARNING:
 # Tests using the multitest feature where failure is expected should *also* be
 # listed in tests/lib/analyzer/analyze_tests.status without the "standalone"
 # prefix.
 
 io/raw_socket_test: Pass, RuntimeError # Issue 28288
@@ skipping 372 matching lines @@
 io/raw_datagram_socket_test: Skip # Flaky.
 io/raw_secure_server_closing_test: Skip # Flaky
 io/raw_secure_server_closing_test: Skip # Flaky.
 io/secure_multiple_client_server_test: Skip # Flaky.
 io/secure_server_closing_test: Skip # Flaky.
 io/secure_server_socket_test: Skip # Flaky.
 io/web_socket_error_test: Skip # Flaky
 io/web_socket_ping_test: Skip # Flaky.
 io/web_socket_test: Skip # Flaky.
 no_support_debugger_test: Skip # kernel-service snapshot not compatible with flag disabled
-package/scenarios/invalid/*: DartkCrash # Issue 30110
 
 regress_29350_test: MissingCompileTimeError
 assert_test: RuntimeError
 io/compile_all_test: Crash
 io/http_cookie_test: RuntimeError
 io/http_proxy_advanced_test: RuntimeError
 io/socket_many_connections_test: RuntimeError
 map_insert_remove_oom_test: Crash
 package/package1_test: CompileTimeError
 package/package_test: CompileTimeError
 package/scenarios/invalid/invalid_utf8_test: CompileTimeError
 package/scenarios/invalid/non_existent_packages_file_test: CompileTimeError
 package/scenarios/invalid/same_package_twice_test: CompileTimeError
-package/scenarios/packages_dir_only/packages_dir_only_test: CompileTimeError
 
 [ $compiler == dartkp ]
 causal_async_stack_test: Fail
 
 [ $runtime == flutter ]
 io/raw_datagram_socket_test: Crash # Flutter Issue 9115
 verbose_gc_to_bmu_test: RuntimeError # Flutter Issue 9115
 io/process_check_arguments_test: RuntimeError # Flutter Issue 9115
 io/process_working_directory_test: RuntimeError # Flutter Issue 9115
 io/process_run_output_test: RuntimeError # Flutter Issue 9115
@@ skipping 75 matching lines @@
 package/package_test: Fail # Unable to parse package files Flutter Issue 9115
 #unboxed_int_converter_test: Fail # Unable to parse package files Flutter Issue 9115
 io/process_run_output_test: Fail # Unable to parse package files Flutter Issue 9115
 
 io/dependency_graph_test: CompileTimeError # Imports dart:mirrors
 io/skipping_dart2js_compilations_test: CompileTimeError # Uses mirrors
 io/status_file_parser_test: CompileTimeError # Uses mirrors
 io/test_harness_analyzer_test: CompileTimeError # Uses mirrors
 io/test_runner_test: CompileTimeError # Uses mirrors
 status_expression_test: CompileTimeError # Uses mirrors