non standard WebIDL dictionary methods.

Chrome IDLs use non standard operations in dictionaries. The following does not pass the checker http://www.w3.org/2009/07/webidl-check

```
[noinline_doc] dictionary AppWindow {
  // Focus the window.
  static void focus();

  // Fullscreens the window.
  static void fullscreen();
};
```

From this patch all Chrome IDLs now parse `98 PASSED, 0 FAILED, 4 ERRORS`

```
unittest-suite-wait-for-done
PASS: Test valid web idl files Testing test/idl/valid/allowany.widl
PASS: Test valid web idl files Testing test/idl/valid/array.widl
PASS: Test valid web idl files Testing test/idl/valid/attributes.widl
PASS: Test valid web idl files Testing test/idl/valid/callback.widl
PASS: Test valid web idl files Testing test/idl/valid/caller.widl
ERROR: Test valid web idl files Testing test/idl/valid/constants.widl
  Test failed: Caught line 10, character 22: expected '-', 'null', 'Infinity', float, integer, 'true', 'false' or 'NaN', got '.'.
PASS: Test valid web idl files Testing test/idl/valid/constructor.widl
PASS: Test valid web idl files Testing test/idl/valid/dictionary-inherits.widl
PASS: Test valid web idl files Testing test/idl/valid/dictionary.widl
PASS: Test valid web idl files Testing test/idl/valid/documentation-dos.widl
PASS: Test valid web idl files Testing test/idl/valid/documentation.widl
PASS: Test valid web idl files Testing test/idl/valid/enum.widl
PASS: Test valid web idl files Testing test/idl/valid/equivalent-decl.widl
PASS: Test valid web idl files Testing test/idl/valid/exception-inheritance.widl
PASS: Test valid web idl files Testing test/idl/valid/exception.widl
PASS: Test valid web idl files Testing test/idl/valid/getter-setter.widl
PASS: Test valid web idl files Testing test/idl/valid/identifier-qualified-names.widl
PASS: Test valid web idl files Testing test/idl/valid/implements.widl
PASS: Test valid web idl files Testing test/idl/valid/indexed-properties.widl
PASS: Test valid web idl files Testing test/idl/valid/inherits-getter.widl
PASS: Test valid web idl files Testing test/idl/valid/interface-inherits.widl
ERROR: Test valid web idl files Testing test/idl/valid/iterator.widl
  Test failed: Caught line 5, character 19: expected '(', got ';'.
PASS: Test valid web idl files Testing test/idl/valid/mapclass.widl
PASS: Test valid web idl files Testing test/idl/valid/namedconstructor.widl
PASS: Test valid web idl files Testing test/idl/valid/nointerfaceobject.widl
PASS: Test valid web idl files Testing test/idl/valid/nullable.widl
PASS: Test valid web idl files Testing test/idl/valid/nullableobjects.widl
PASS: Test valid web idl files Testing test/idl/valid/operation-optional-arg.widl
PASS: Test valid web idl files Testing test/idl/valid/overloading.widl
PASS: Test valid web idl files Testing test/idl/valid/overridebuiltins.widl
PASS: Test valid web idl files Testing test/idl/valid/partial-interface.widl
PASS: Test valid web idl files Testing test/idl/valid/primitives.widl
PASS: Test valid web idl files Testing test/idl/valid/prototyperoot.widl
PASS: Test valid web idl files Testing test/idl/valid/putforwards.widl
PASS: Test valid web idl files Testing test/idl/valid/reg-operations.widl
PASS: Test valid web idl files Testing test/idl/valid/replaceable.widl
PASS: Test valid web idl files Testing test/idl/valid/sequence.widl
ERROR: Test valid web idl files Testing test/idl/valid/serializer.widl
  Test failed: Caught line 8, character 13: expected identifier, '?', '(', '[' or spaces, got ';'.
ERROR: Test valid web idl files Testing test/idl/valid/static.widl
  Test failed: Caught line 9, character 10: expected 'float', 'DOMString', 'Date', 'octet', identifier, 'any?', 'double', 'unrestricted', 'any', 'object', 'boolean', '(', 'sequence', 'void', 'short', 'long', 'unsigned' or 'byte', got 'r'.
PASS: Test valid web idl files Testing test/idl/valid/stringifier-attribute.widl
PASS: Test valid web idl files Testing test/idl/valid/stringifier-custom.widl
PASS: Test valid web idl files Testing test/idl/valid/stringifier.widl
PASS: Test valid web idl files Testing test/idl/valid/treatasnull.widl
PASS: Test valid web idl files Testing test/idl/valid/treatasundefined.widl
PASS: Test valid web idl files Testing test/idl/valid/typedef.widl
PASS: Test valid web idl files Testing test/idl/valid/typesuffixes.widl
PASS: Test valid web idl files Testing test/idl/valid/uniontype.widl
PASS: Test valid web idl files Testing test/idl/valid/variadic-operations.widl
PASS: Test invalid web idl files Testing test/idl/invalid/enum.widl
PASS: Test invalid web idl files Testing test/idl/invalid/module.widl
PASS: Test invalid web idl files Testing test/idl/invalid/nonnullableany.widl
PASS: Test invalid web idl files Testing test/idl/invalid/nonnullableobjects.widl
PASS: Test invalid web idl files Testing test/idl/invalid/raises.widl
PASS: Test invalid web idl files Testing test/idl/invalid/scopedname.widl
PASS: Test invalid web idl files Testing test/idl/invalid/sequenceAsAttribute.widl
PASS: Test invalid web idl files Testing test/idl/invalid/special-omittable.widl
PASS: Test invalid web idl files Testing test/idl/invalid/stringconstants.idl
PASS: Test chrome idl files Testing test/../idl/alarms.idl
PASS: Test chrome idl files Testing test/../idl/app_current_window_internal.idl
PASS: Test chrome idl files Testing test/../idl/app_runtime.idl
PASS: Test chrome idl files Testing test/../idl/app_window.idl
PASS: Test chrome idl files Testing test/../idl/audio.idl
PASS: Test chrome idl files Testing test/../idl/autotest_private.idl
PASS: Test chrome idl files Testing test/../idl/bluetooth.idl
PASS: Test chrome idl files Testing test/../idl/braille_display_private.idl
PASS: Test chrome idl files Testing test/../idl/desktop_capture.idl
PASS: Test chrome idl files Testing test/../idl/developer_private.idl
PASS: Test chrome idl files Testing test/../idl/diagnostics.idl
PASS: Test chrome idl files Testing test/../idl/dial.idl
PASS: Test chrome idl files Testing test/../idl/dns.idl
PASS: Test chrome idl files Testing test/../idl/downloads.idl
PASS: Test chrome idl files Testing test/../idl/downloads_internal.idl
PASS: Test chrome idl files Testing test/../idl/experimental_discovery.idl
PASS: Test chrome idl files Testing test/../idl/experimental_identity.idl
PASS: Test chrome idl files Testing test/../idl/experimental_idltest.idl
PASS: Test chrome idl files Testing test/../idl/feedback_private.idl
PASS: Test chrome idl files Testing test/../idl/file_system.idl
PASS: Test chrome idl files Testing test/../idl/identity.idl
PASS: Test chrome idl files Testing test/../idl/identity_private.idl
PASS: Test chrome idl files Testing test/../idl/location.idl
PASS: Test chrome idl files Testing test/../idl/log_private.idl
PASS: Test chrome idl files Testing test/../idl/mdns.idl
PASS: Test chrome idl files Testing test/../idl/media_galleries.idl
PASS: Test chrome idl files Testing test/../idl/media_galleries_private.idl
PASS: Test chrome idl files Testing test/../idl/music_manager_private.idl
PASS: Test chrome idl files Testing test/../idl/notifications.idl
PASS: Test chrome idl files Testing test/../idl/power.idl
PASS: Test chrome idl files Testing test/../idl/push_messaging.idl
PASS: Test chrome idl files Testing test/../idl/recovery_private.idl
PASS: Test chrome idl files Testing test/../idl/rtc_private.idl
PASS: Test chrome idl files Testing test/../idl/serial.idl
PASS: Test chrome idl files Testing test/../idl/signed_in_devices.idl
PASS: Test chrome idl files Testing test/../idl/socket.idl
PASS: Test chrome idl files Testing test/../idl/sockets_udp.idl
PASS: Test chrome idl files Testing test/../idl/sync_file_system.idl
PASS: Test chrome idl files Testing test/../idl/system_cpu.idl
PASS: Test chrome idl files Testing test/../idl/system_display.idl
PASS: Test chrome idl files Testing test/../idl/system_indicator.idl
PASS: Test chrome idl files Testing test/../idl/system_memory.idl
PASS: Test chrome idl files Testing test/../idl/system_storage.idl
PASS: Test chrome idl files Testing test/../idl/tab_capture.idl
PASS: Test chrome idl files Testing test/../idl/usb.idl

98 PASSED, 0 FAILED, 4 ERRORS
```