Silence invasive deprecation warnings, opt-in for warnings

ApcUniversalClassLoader.php

@@ -11,7 +11,7 @@
 
 namespace Symfony\Component\ClassLoader;
 
-trigger_error('The '.__NAMESPACE__.'\ApcUniversalClassLoader class is deprecated since version 2.7 and will be removed in 3.0. Use the Symfony\Component\ClassLoader\ApcClassLoader class instead.', E_USER_DEPRECATED);
+@trigger_error('The '.__NAMESPACE__.'\ApcUniversalClassLoader class is deprecated since version 2.7 and will be removed in 3.0. Use the Symfony\Component\ClassLoader\ApcClassLoader class instead.', E_USER_DEPRECATED);
 
 /**
  * ApcUniversalClassLoader implements a "universal" autoloader cached in APC for PHP 5.3.

DebugClassLoader.php

@@ -11,7 +11,7 @@
 
 namespace Symfony\Component\ClassLoader;
 
-trigger_error('The '.__NAMESPACE__.'\DebugClassLoader class is deprecated since version 2.4 and will be removed in 3.0. Use the Symfony\Component\Debug\DebugClassLoader class instead.', E_USER_DEPRECATED);
+@trigger_error('The '.__NAMESPACE__.'\DebugClassLoader class is deprecated since version 2.4 and will be removed in 3.0. Use the Symfony\Component\Debug\DebugClassLoader class instead.', E_USER_DEPRECATED);
 
 /**
  * Autoloader checking if the class is really defined in the file found.

DebugUniversalClassLoader.php

@@ -11,7 +11,7 @@
 
 namespace Symfony\Component\ClassLoader;
 
-trigger_error('The '.__NAMESPACE__.'\DebugUniversalClassLoader class is deprecated since version 2.4 and will be removed in 3.0. Use the Symfony\Component\Debug\DebugClassLoader class instead.', E_USER_DEPRECATED);
+@trigger_error('The '.__NAMESPACE__.'\DebugUniversalClassLoader class is deprecated since version 2.4 and will be removed in 3.0. Use the Symfony\Component\Debug\DebugClassLoader class instead.', E_USER_DEPRECATED);
 
 /**
  * Checks that the class is actually declared in the included file.

UniversalClassLoader.php

@@ -11,7 +11,7 @@
 
 namespace Symfony\Component\ClassLoader;
 
-trigger_error('The '.__NAMESPACE__.'\UniversalClassLoader class is deprecated since version 2.7 and will be removed in 3.0. Use the Symfony\Component\ClassLoader\ClassLoader class instead.', E_USER_DEPRECATED);
+@trigger_error('The '.__NAMESPACE__.'\UniversalClassLoader class is deprecated since version 2.7 and will be removed in 3.0. Use the Symfony\Component\ClassLoader\ClassLoader class instead.', E_USER_DEPRECATED);
 
 /**
  * UniversalClassLoader implements a "universal" autoloader for PHP 5.3.