Implement simple switch statements as nested if/else.

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.
 
 package/invalid_uri_test: Fail, OK # CompileTimeErrors intentionally
@@ skipping 160 matching lines @@
 
 [ $compiler == dart2js && $cps_ir ]
 io/addlatexhash_test: Crash # (try {test(tempDir.path);}finally {tempDir.delete(recursive:true);}): try/finally
 io/create_recursive_test: Crash # (try {var file=new F...  try/finally
 io/directory_list_pause_test: Crash # Invalid argument(s)
 io/file_test: Crash # Instance of 'TypeOperator': type check unimplemented for _Nullary.
 io/file_typed_data_test: Crash # Invalid argument(s)
 io/http_bind_test: Crash # (testBindShared(Stri...  cannot handle async/sync*/async* functions
 io/http_cookie_date_test: Crash # Invalid argument(s)
 io/http_headers_test: Crash # (switch (name.length...  Unhandled node
-io/http_parser_test: Crash # (switch (_state){cas...  Unhandled node
 io/http_proxy_test: Crash # Invalid argument(s)
 io/https_bad_certificate_test: Crash # (main()async{var cli...  cannot handle async/sync*/async* functions
 io/issue_22636_test: Crash # (test()async{server=...  cannot handle async/sync*/async* functions
 io/issue_22637_test: Crash # (test()async{server=...  cannot handle async/sync*/async* functions
 io/platform_resolved_executable_test/01: Crash # (try {test(tempDir);}finally {tempDir.deleteSync(recursive:true);}): try/finally
 io/platform_resolved_executable_test/02: Crash # (try {test(tempDir);}finally {tempDir.deleteSync(recursive:true);}): try/finally
 io/platform_resolved_executable_test/04: Crash # (try {test(tempDir);}finally {tempDir.deleteSync(recursive:true);}): try/finally
 io/platform_resolved_executable_test/05: Crash # (try {test(tempDir);}finally {tempDir.deleteSync(recursive:true);}): try/finally
-io/raw_datagram_socket_test: Crash # (switch (event){case...  Unhandled node
 io/raw_secure_server_closing_test: Crash # Invalid argument(s)
 io/raw_secure_server_socket_test: Crash # Invalid argument(s)
-io/raw_secure_socket_pause_test: Crash # (switch (event){case...  Unhandled node
-io/raw_secure_socket_test: Crash # (switch (event){case...  Unhandled node
-io/raw_server_socket_cancel_test: Crash # (switch (event){case...  Unhandled node
-io/raw_socket_cross_process_test: Crash # (switch (event){case...  Unhandled node
 io/raw_socket_test: Crash # Instance of 'TypeOperator': type check unimplemented for _Nullary.
 io/raw_socket_typed_data_test: Crash # Invalid argument(s)
-io/regress_21160_test: Crash # (switch (event){case...  Unhandled node
-io/secure_client_raw_server_test: Crash # (switch (event){case...  Unhandled node
 io/secure_server_closing_test: Crash # Invalid argument(s)
 io/secure_server_socket_test: Crash # Invalid argument(s)
-io/secure_socket_bad_data_test: Crash # (switch (event){case...  Unhandled node
 io/skipping_dart2js_compilations_test: Crash # (switch (segment){ca...  Unhandled node
 io/socket_bind_test: Crash # (testListenCloseList...  cannot handle async/sync*/async* functions
-io/socket_close_test: Crash # (switch (_mode){case...  Unhandled node
 io/socket_exception_test: Crash # Invalid argument(s)
 io/socket_source_address_test: Crash # (Future testConnect(...  cannot handle async/sync*/async* functions
 io/socket_upgrade_to_secure_test: Crash # Invalid argument(s)
-io/test_extension_fail_test: Crash # (switch (Platform.op...  Unhandled node
-io/test_extension_test: Crash # (switch (Platform.op...  Unhandled node
 io/test_runner_test: Crash # (switch (arguments[0...  Unhandled node
 priority_queue_stress_test: RuntimeError # Cannot read property 'any$1' of undefined