function cleanBackgroundColor (projectRoot, projectConfig, locations) {
    const platformProjDir = path.relative(projectRoot, locations.xcodeCordovaProj);

    const contentsJSON = {
        colors: [{
            idiom: 'universal',
            color: colorPreferenceToComponents(null)
        }],
        info: {
            author: 'Xcode',
            version: 1
        }
    };

    const backgroundColorDir = getBackgroundColorDir(projectRoot, platformProjDir);
    if (backgroundColorDir) {
        events.emit('verbose', 'Cleaning Background Color color set Contents.json');
        fs.writeFileSync(path.join(projectRoot, backgroundColorDir, 'Contents.json'),
            JSON.stringify(contentsJSON, null, 2));
    }

    const splashBackgroundColorDir = getSplashScreenBackgroundColorDir(projectRoot, platformProjDir);
    if (splashBackgroundColorDir) {
        events.emit('verbose', 'Cleaning Splash Screen Background Color color set Contents.json');
        fs.writeFileSync(path.join(projectRoot, splashBackgroundColorDir, 'Contents.json'),
            JSON.stringify(contentsJSON, null, 2));
    }

    const statusBarBackgroundColorDir = getStatusBarBackgroundColorDir(projectRoot, platformProjDir);
    if (statusBarBackgroundColorDir) {
        events.emit('verbose', 'Cleaning Status Bar Background Color color set Contents.json');
        fs.writeFileSync(path.join(projectRoot, statusBarBackgroundColorDir, 'Contents.json'),
            JSON.stringify(contentsJSON, null, 2));
    }
}
Resets the background color Contents.json in xcassets to default.

@param {string} projectRoot Path to the project root
@param {Object} projectConfig The project's config.xml
@param {Object} locations A dictionary containing useful location paths