Merge branch '3.4' into 4.4

* 3.4:
  [FrameworkBundle] display actual target for error in AssetsInstallCommand
  Remove patches for Doctrine bugs and deprecations
  [DI][EventDispatcher] added contract for implementation

Author: nicolas-grekas

composer.json

@@ -42,7 +42,7 @@
         "doctrine/cache": "~1.6",
         "doctrine/collections": "~1.0",
         "doctrine/data-fixtures": "1.0.*",
-        "doctrine/dbal": "~2.4,<=2.10.2",
+        "doctrine/dbal": "~2.4",
         "doctrine/orm": "^2.6.3",
         "doctrine/reflection": "~1.0"
     },