application-manager: fix expose-loader

[paul-marechal]

For some reason the loader causes some applications to fail at runtime.

Use an alternative writing for one of the injected string of code.

How to test

Should fix the browser application start failure for this repository:

https://github.com/theia-ide/theia-trace-extension/tree/b4855ec742015d08bbec0d3d549b83eb61df8ec5

Linux-only:

• Clone the repo.
• Run yarn.
• Run yarn download:server
• Run yarn --cwd examples/browser start
• Open your browser at localhost:3000, it should fail because of some ReferenceError: global.
• Edit node_modules/@theia/application-manager/lib/expose-loader.js and replace the same string as this PR.
• Run yarn --cwd examples/browser
• Run yarn --cwd examples/browser start
• Open your browser at localhost:3000, it should work.

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines

[vince-fugnitto]

I confirmed the error on master using the trace extension, and confirmed that this pull-request correctly fixes the problem:

Note that in order to produce the error on the trace extension the webpack.config.js was modified to:

/**
 * This file can be edited to customize webpack configuration.
 * To reset delete this file and rerun theia build again.
 */
// @ts-check
const config = require('./gen-webpack.config.js');

/**
 * Expose bundled modules on window.theia.moduleName namespace, e.g.
 * window['theia']['@theia/core/lib/common/uri'].
 * Such syntax can be used by external code, for instance, for testing.
 * */
config.module.rules.push({
    test: /\.js$/,
    loader: require.resolve('@theia/application-manager/lib/expose-loader')
});

module.exports = config;