Prevent fatal str_pos() error in dist parsing.

[grasmash]

I'm encountering the following error:

Adding VCS repository npm-asset/defined
Adding VCS repository npm-asset/deps-sort
Adding VCS repository npm-asset/domain-browser
Adding VCS repository npm-asset/duplexer2

  [ErrorException]
  strpos() expects parameter 1 to be string, array given

Exception trace:
 () at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Converter/NpmPackageUtil.php:72
 Composer\Util\ErrorHandler::handle() at n/a:n/a
 strpos() at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Converter/NpmPackageUtil.php:72
 Fxp\Composer\AssetPlugin\Converter\NpmPackageUtil::convertDist() at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Converter/NpmPackageConverter.php:53
 Fxp\Composer\AssetPlugin\Converter\NpmPackageConverter->Fxp\Composer\AssetPlugin\Converter\{closure}() at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Converter/PackageUtil.php:162
 Fxp\Composer\AssetPlugin\Converter\PackageUtil::convertArrayKey() at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Converter/AbstractPackageConverter.php:93
 Fxp\Composer\AssetPlugin\Converter\AbstractPackageConverter->convertKey() at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Converter/AbstractPackageConverter.php:66
 Fxp\Composer\AssetPlugin\Converter\AbstractPackageConverter->convertData() at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Converter/AbstractPackageConverter.php:47
 Fxp\Composer\AssetPlugin\Converter\AbstractPackageConverter->convert() at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Repository/NpmRepository.php:132
 Fxp\Composer\AssetPlugin\Repository\NpmRepository->createArrayRepositoryConfig() at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Repository/NpmRepository.php:79
 Fxp\Composer\AssetPlugin\Repository\NpmRepository->createVcsRepositoryConfig() at /Users/matthew.grasmick/Sites/acquia/lightning/vendor/fxp/composer-asset-plugin/Repository/AbstractAssetsRepository.php:136
 Fxp\Composer\AssetPlugin\Repository\AbstractAssetsRepository->whatProvides() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/DependencyResolver/Pool.php:199
 Composer\DependencyResolver\Pool->computeWhatProvides() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/DependencyResolver/Pool.php:188
 Composer\DependencyResolver\Pool->whatProvides() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/DependencyResolver/RuleSetGenerator.php:161
 Composer\DependencyResolver\RuleSetGenerator->whitelistFromPackage() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/DependencyResolver/RuleSetGenerator.php:273
 Composer\DependencyResolver\RuleSetGenerator->whitelistFromJobs() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/DependencyResolver/RuleSetGenerator.php:324
 Composer\DependencyResolver\RuleSetGenerator->getRulesFor() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/DependencyResolver/Solver.php:208
 Composer\DependencyResolver\Solver->solve() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/Installer.php:510
 Composer\Installer->doInstall() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/Installer.php:223
 Composer\Installer->run() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/Command/InstallCommand.php:134
 Composer\Command\InstallCommand->execute() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/vendor/symfony/console/Command/Command.php:259
 Symfony\Component\Console\Command\Command->run() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/vendor/symfony/console/Application.php:844
 Symfony\Component\Console\Application->doRunCommand() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/vendor/symfony/console/Application.php:192
 Symfony\Component\Console\Application->doRun() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/Console/Application.php:166
 Composer\Console\Application->doRun() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/vendor/symfony/console/Application.php:123
 Symfony\Component\Console\Application->run() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/src/Composer/Console/Application.php:99
 Composer\Console\Application->run() at phar:///usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar/bin/composer:43
 require() at /usr/local/Cellar/composer/1.0.0-alpha8/libexec/composer.phar:25

install [--prefer-source] [--prefer-dist] [--dry-run] [--dev] [--no-dev] [--no-plugins] [--no-custom-installers] [--no-autoloader] [--no-scripts] [--no-progress] [-v|vv|vvv|--verbose] [-o|--optimize-autoloader] [-a|--classmap-authoritative] [--ignore-platform-reqs] [--] [<packages>]...

I expect that an upstream package has malformed data, or else we're just not properly account for all possible data structures. This commit circumvent the problem. It'd be nice to log a warning, but I'm not familiar with the correct composer method for doing so.

[grasmash]

@francoispluchino I'm not familiar with how to avoid reducing code coverage, but I can confirm that this change does mitigate the specific issue that I've raised. You could reproduce it by requiring the following packages:

        "npm-asset/bb-collection-view": "1.0.6",
        "npm-asset/dropzone": "4.3.0",
        "npm-asset/es6-promise": "3.2.1",
        "npm-asset/jquery-appear-poetic": "0.3.6"

[grasmash]

@francoispluchino Does this PR require any changes before being merged?

[francoispluchino]

I will see this PR tomorrow.