Merge branch '4.4'

* 4.4:
  Update GitHub PR template
  [DI] fix related to preloading
  [HttpKernel] fix compat with legacy DebugClassLoader
  [WebProfilerBundle] Assign automatic colors to custom Stopwatch categories
  [DI] use dirname() when possible
  Simplify usage of dirname()
  Remove Google references when not needed
  Simplify usage of dirname()
  don't dump a scalar tag value on its own line
  Remove Google references when not needed
  [DI] fix Preloader
  [HttpClient] fix calling the buffer-enabling callback
  [HttpClient] fix php notice on push
  do not perform string operations on null
  Require exact match when reading from stdin with a dash

Author: nicolas-grekas

Tests/Resources/TranslationFilesTest.php

@@ -29,15 +29,15 @@ public function provideTranslationFiles()
     {
         return array_map(
             function ($filePath) { return (array) $filePath; },
-            glob(\dirname(\dirname(__DIR__)).'/Resources/translations/*.xlf')
+            glob(\dirname(__DIR__, 2).'/Resources/translations/*.xlf')
         );
     }
 
     public function testNorwegianAlias()
     {
         $this->assertFileEquals(
-            \dirname(\dirname(__DIR__)).'/Resources/translations/security.nb.xlf',
-            \dirname(\dirname(__DIR__)).'/Resources/translations/security.no.xlf',
+            \dirname(__DIR__, 2).'/Resources/translations/security.nb.xlf',
+            \dirname(__DIR__, 2).'/Resources/translations/security.no.xlf',
             'The NO locale should be an alias for the NB variant of the Norwegian language.'
         );
     }