Bug Report

Current Behavior
Babel dynamic import _interopRequireWildcard function fail if imported obj/ modules is pure string (e.g. base64 encoded image), because cache (WeakMap) doesn't accept string as key (only accept object).

Input Code
Ref: #10161

Expected behavior/code
_interopRequireWildcard should take care string module (url-loader/file-loader) also.

Environment

• @babel/core": "^7.6.4"
• node 10.15
• @babel/plugin-transform-runtime: 7.6.2
• url-loader : ^2.2.0

Possible Solution
Consider a different cache mechanism (e.g. Map/ no cache for string)