Source map + minimizer results in silent failure

[webpack-bot]

Bug report

What is the current behavior?
Using source map with minimizer causes silent failure. Output file not created. No console output.

If the current behavior is a bug, please provide the steps to reproduce.

1. Create empty file 1.js
2. Create webpack.config.js file with contents:

const TerserPlugin = require('terser-webpack-plugin');
module.exports = {
    devtool:  'source-map',
    entry: './1.js',
    resolve: {
        extensions: ['.js']
    },
    output: {
        filename: 'main.js',
        path: __dirname,
    },
    optimization: {
        minimize: true,
        minimizer: [
            new TerserPlugin({
                sourceMap: true,
            }),
        ],
    }
};

3. Run webpack --config webpack.config.js

What is the expected behavior?
Output file main.js is created. Console output.

Other relevant information:
webpack version: 4.35.0
Node.js version: 10.15.3
terser-webpack-plugin version: 1.3.0
Operating System: Win 10

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This issue was moved from webpack/webpack#9338 by @sokra. Original issue was by @underflow00.

[alexander-akait]

Close in favor #100