Merge branch '2.8' into 3.0

* 2.8:
  [Process] Fix stream_select priority when writing to stdin
  [Form] NumberToLocalizedStringTransformer should return floats when possible
  [Form] remove useless code in ChoiceType
  [DependencyInjection] Enabled alias for service_container

Conflicts:
	src/Symfony/Component/DependencyInjection/Tests/Compiler/ReplaceAliasByActualDefinitionPassTest.php
	src/Symfony/Component/Form/Extension/Core/Type/ChoiceType.php

Author: nicolas-grekas

Compiler/ReplaceAliasByActualDefinitionPass.php

@@ -42,6 +42,10 @@ public function process(ContainerBuilder $container)
         foreach ($container->getAliases() as $id => $alias) {
             $aliasId = (string) $alias;
 
+            if ('service_container' === $aliasId) {
+                continue;
+            }
+
             try {
                 $definition = $container->getDefinition($aliasId);
             } catch (InvalidArgumentException $e) {

Tests/Compiler/ReplaceAliasByActualDefinitionPassTest.php

@@ -34,6 +34,8 @@ public function testProcess()
         $container->setAlias('a_alias', 'a');
         $container->setAlias('b_alias', 'b');
 
+        $container->setAlias('container', 'service_container');
+
         $this->process($container);
 
         $this->assertTrue($container->has('a'), '->process() does nothing to public definitions.');
@@ -44,6 +46,8 @@ public function testProcess()
             '->process() replaces alias to actual.'
         );
 
+        $this->assertTrue($container->has('container'));
+
         $resolvedFactory = $aDefinition->getFactory(false);
         $this->assertSame('b_alias', (string) $resolvedFactory[0]);
     }