Merge branch '2.8' into 3.1

* 2.8:
  [ClassLoader] Use only forward slashes in generated class map
  ensure the proper context for nested validations
  bug #20653 [WebProfilerBundle] Profiler includes ghost panels

ClassCollectionLoader.php

@@ -60,7 +60,7 @@ class ClassCollectionLoader
             throw new \RuntimeException(sprintf('Class Collection Loader was not able to create directory "%s"', $cacheDir));
         }
         $cacheDir = rtrim(realpath($cacheDir) ?: $cacheDir, '/'.DIRECTORY_SEPARATOR);
-        $cache = $cacheDir.DIRECTORY_SEPARATOR.$name.$extension;
+        $cache = $cacheDir.'/'.$name.$extension;
 
         // auto-reload
         $reload = false;
@@ -108,7 +108,7 @@ class ClassCollectionLoader
 REGEX;
         $dontInlineRegex = str_replace('.', $spacesRegex, $dontInlineRegex);
 
-        $cacheDir = explode(DIRECTORY_SEPARATOR, $cacheDir);
+        $cacheDir = explode('/', str_replace(DIRECTORY_SEPARATOR, '/', $cacheDir));
         $files = array();
         $content = '';
         foreach (self::getOrderedClasses($classes) as $class) {
@@ -120,7 +120,7 @@ REGEX;
             $c = file_get_contents($file);
 
             if (preg_match($dontInlineRegex, $c)) {
-                $file = explode(DIRECTORY_SEPARATOR, $file);
+                $file = explode('/', str_replace(DIRECTORY_SEPARATOR, '/', $file));
 
                 for ($i = 0; isset($file[$i], $cacheDir[$i]); ++$i) {
                     if ($file[$i] !== $cacheDir[$i]) {
@@ -128,11 +128,11 @@ REGEX;
                     }
                 }
                 if (1 >= $i) {
-                    $file = var_export(implode(DIRECTORY_SEPARATOR, $file), true);
+                    $file = var_export(implode('/', $file), true);
                 } else {
                     $file = array_slice($file, $i);
-                    $file = str_repeat('..'.DIRECTORY_SEPARATOR, count($cacheDir) - $i).implode(DIRECTORY_SEPARATOR, $file);
-                    $file = '__DIR__.'.var_export(DIRECTORY_SEPARATOR.$file, true);
+                    $file = str_repeat('../', count($cacheDir) - $i).implode('/', $file);
+                    $file = '__DIR__.'.var_export('/'.$file, true);
                 }
 
                 $c = "\nnamespace {require $file;}";