Remove alias loading code which is no longer necessary

Since alias packages do not get dumped anymore, only original packages
will ever be in Filesystem repositories. Alias are created on the fly
based on alias info in the composer.json/composer.lock and on branch
alias data in the original package.

src/Composer/Repository/FilesystemRepository.php

@@ -55,33 +55,11 @@ class FilesystemRepository extends ArrayRepository implements WritableRepository
             throw new \UnexpectedValueException('Could not parse package list from the '.$this->file->getPath().' repository');
         }
 
-        $aliases = array();
-
         $loader = new ArrayLoader();
         foreach ($packages as $packageData) {
             $package = $loader->load($packageData);
-
-            // aliases need to be looked up in the end to set up references correctly
-            if ($this instanceof InstalledRepositoryInterface && !empty($packageData['alias'])) {
-                $aliases[] = array(
-                    'package' => $package,
-                    'alias' => $packageData['alias'],
-                    'alias_pretty' => $packageData['alias_pretty']
-                );
-            }
-
             $this->addPackage($package);
         }
-
-        foreach ($aliases as $aliasData) {
-            $temporaryPackage = $aliasData['package'];
-
-            $package = $this->findPackage($temporaryPackage->getName(), $temporaryPackage->getVersion());
-
-            $package->setAlias($aliasData['alias']);
-            $package->setPrettyAlias($aliasData['alias_pretty']);
-            $this->addPackage($this->createAliasPackage($package, $aliasData['alias'], $aliasData['alias_pretty']));
-        }
     }
 
     public function reload()