Fix node.error() handling

[kazuhitoyokoi]

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Proposed changes

Current node which is generated from swagger definition cannot catch error because node.error() has only first argument. To solve the problem, I added msg variable as the second argument.

Checklist

• I have read the contribution guidelines
• For non-bugfix PRs, I have discussed this change on the mailing list/slack team.
• I have run grunt to verify the unit tests pass
• I have added suitable unit tests to cover the new/changed functionality

[coveralls]

Coverage remained the same at 77.812% when pulling f39026b on kazuhitoyokoi:master-fixnodeerror into 6b88422 on node-red:master.

[kazuhitoyokoi]

@HiroyasuNishiyama Could you consider merging the pull request before our summer vacation?