No need to alias platform packages before the repository set as the pool builder already does it

src/Composer/DependencyResolver/PoolBuilder.php

@@ -170,7 +170,6 @@ class PoolBuilder
             $aliasPackage = new AliasPackage($basePackage, $alias['alias_normalized'], $alias['alias']);
             $aliasPackage->setRootPackageAlias(true);
 
-            $package->getRepository()->addPackage($aliasPackage); // TODO do we need this?
             $this->packages[] = $aliasPackage;
             $this->aliasMap[spl_object_hash($aliasPackage->getAliasOf())][$index+1] = $aliasPackage;
         }

src/Composer/Installer.php

@@ -697,8 +697,6 @@ class Installer
      */
     private function createRepositorySet(PlatformRepository $platformRepo, array $rootAliases = array(), $lockedRepository = null)
     {
-        $this->aliasPlatformPackages($platformRepo, $rootAliases);
-
         // TODO what's the point of rootConstraints at all, we generate the package pool taking them into account anyway?
         // TODO maybe we can drop the lockedRepository here
         // TODO if this gets called in doInstall, this->update is still true?!
@@ -830,25 +828,6 @@ class Installer
         return $normalizedAliases;
     }
 
-    /**
-     * @param PlatformRepository $platformRepo
-     * @param array              $aliases
-     */
-    private function aliasPlatformPackages(PlatformRepository $platformRepo, $aliases)
-    {
-        // TODO should the repository set do this?
-        foreach ($aliases as $packageName => $versions) {
-            foreach ($versions as $version => $alias) {
-                $packages = $platformRepo->findPackages($packageName, $version);
-                foreach ($packages as $package) {
-                    $aliasPackage = new AliasPackage($package, $alias['alias_normalized'], $alias['alias']);
-                    $aliasPackage->setRootPackageAlias(true);
-                    $platformRepo->addPackage($aliasPackage);
-                }
-            }
-        }
-    }
-
     /**
      * @param  PackageInterface $package
      * @return bool