minor #22843 use getProjectDir() when possible (xabbuh)

This PR was merged into the 3.3 branch.

Discussion
----------

use getProjectDir() when possible

| Q             | A
| ------------- | ---
| Branch?       | 3.3
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | continues #22315
| License       | MIT
| Doc PR        |

Commits
-------

a8e298a66c use getProjectDir() when possible

Author: fabpot

Command/AboutCommand.php

@@ -46,7 +46,6 @@ protected function execute(InputInterface $input, OutputInterface $output)
 
         /** @var $kernel KernelInterface */
         $kernel = $this->getContainer()->get('kernel');
-        $baseDir = realpath($kernel->getRootDir().DIRECTORY_SEPARATOR.'..');
 
         $io->table(array(), array(
             array('<info>Symfony</>'),
@@ -62,9 +61,9 @@ protected function execute(InputInterface $input, OutputInterface $output)
             array('Environment', $kernel->getEnvironment()),
             array('Debug', $kernel->isDebug() ? 'true' : 'false'),
             array('Charset', $kernel->getCharset()),
-            array('Root directory', self::formatPath($kernel->getRootDir(), $baseDir)),
-            array('Cache directory', self::formatPath($kernel->getCacheDir(), $baseDir).' (<comment>'.self::formatFileSize($kernel->getCacheDir()).'</>)'),
-            array('Log directory', self::formatPath($kernel->getLogDir(), $baseDir).' (<comment>'.self::formatFileSize($kernel->getLogDir()).'</>)'),
+            array('Root directory', self::formatPath($kernel->getRootDir(), $kernel->getProjectDir())),
+            array('Cache directory', self::formatPath($kernel->getCacheDir(), $kernel->getProjectDir()).' (<comment>'.self::formatFileSize($kernel->getCacheDir()).'</>)'),
+            array('Log directory', self::formatPath($kernel->getLogDir(), $kernel->getProjectDir()).' (<comment>'.self::formatFileSize($kernel->getLogDir()).'</>)'),
             new TableSeparator(),
             array('<info>PHP</>'),
             new TableSeparator(),

Command/AssetsInstallCommand.php

@@ -82,9 +82,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
         $targetArg = rtrim($input->getArgument('target'), '/');
 
         if (!is_dir($targetArg)) {
-            $appRoot = $this->getContainer()->getParameter('kernel.root_dir').'/..';
-
-            $targetArg = $appRoot.'/'.$targetArg;
+            $targetArg = $this->getContainer()->getParameter('kernel.project_dir').'/'.$targetArg;
 
             if (!is_dir($targetArg)) {
                 throw new \InvalidArgumentException(sprintf('The target directory "%s" does not exist.', $input->getArgument('target')));