Cannot read property 'toLowerCase' of undefined in normalizeType

**Waterline version**: ^0.13.5
**Node version**: 10.10.1
**NPM version**: 6.4.1
**Operating system**: Windows 10

i want migrate drop with waterline utils and i have error with build schema in sails-mysql i use waterline standalone and waterline utils
i tried both use ``autoMigrations.columnType`` and without it .. any idea ?

Start by reproducing the schema-build error with Waterline standalone, waterline-utils, and the sails-mysql adapter on the reported versions, testing both settings for autoMigrations.columnType. The report does not name source files or tests; done means the migration or schema build no longer raises the undefined toLowerCase error.

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