Merge branch '3.1'

* 3.1: (22 commits)
  [travis] Fix deps=low/high builds
  [Form] Fix depreciation triggers
  fixed CS
  skip test with current phpunit bridge
  Fix for #19183 to add support for new PHP MongoDB extension in sessions.
  [Console] Fix for block() padding formatting after #19189
  [Security][Guard] check if session exist before using it
  bumped Symfony version to 3.1.3
  updated VERSION for 3.1.2
  updated CHANGELOG for 3.1.2
  bumped Symfony version to 3.0.9
  updated VERSION for 3.0.8
  updated CHANGELOG for 3.0.8
  bumped Symfony version to 2.8.9
  updated VERSION for 2.8.8
  updated CHANGELOG for 2.8.8
  bumped Symfony version to 2.7.16
  updated VERSION for 2.7.15
  update CONTRIBUTORS for 2.7.15
  updated CHANGELOG for 2.7.15
  ...

Conflicts:
	src/Symfony/Component/HttpKernel/Kernel.php

Author: nicolas-grekas

Tests/ContainerBuilderTest.php

@@ -58,6 +58,9 @@ public function testDefinitions()
         }
     }
 
+    /**
+     * @requires function Symfony\Bridge\PhpUnit\ErrorAssert::assertDeprecationsAreTriggered
+     */
     public function testCreateDeprecatedService()
     {
         ErrorAssert::assertDeprecationsAreTriggered('The "deprecated_foo" service is deprecated. You should stop using it, as it will soon be removed.', function () {

Tests/ContainerTest.php

@@ -308,7 +308,10 @@ public function testThatCloningIsNotSupported()
         $this->assertTrue($clone->isPrivate());
     }
 
-    /** @group legacy */
+    /**
+     * @group legacy
+     * @requires function Symfony\Bridge\PhpUnit\ErrorAssert::assertDeprecationsAreTriggered
+     */
     public function testUnsetInternalPrivateServiceIsDeprecated()
     {
         $deprecations = array(
@@ -321,7 +324,10 @@ public function testUnsetInternalPrivateServiceIsDeprecated()
         });
     }
 
-    /** @group legacy */
+    /**
+     * @group legacy
+     * @requires function Symfony\Bridge\PhpUnit\ErrorAssert::assertDeprecationsAreTriggered
+     */
     public function testChangeInternalPrivateServiceIsDeprecated()
     {
         $deprecations = array(
@@ -334,7 +340,10 @@ public function testChangeInternalPrivateServiceIsDeprecated()
         });
     }
 
-    /** @group legacy */
+    /**
+     * @group legacy
+     * @requires function Symfony\Bridge\PhpUnit\ErrorAssert::assertDeprecationsAreTriggered
+     */
     public function testCheckExistenceOfAnInternalPrivateServiceIsDeprecated()
     {
         $deprecations = array(
@@ -347,7 +356,10 @@ public function testCheckExistenceOfAnInternalPrivateServiceIsDeprecated()
         });
     }
 
-    /** @group legacy */
+    /**
+     * @group legacy
+     * @requires function Symfony\Bridge\PhpUnit\ErrorAssert::assertDeprecationsAreTriggered
+     */
     public function testRequestAnInternalSharedPrivateServiceIsDeprecated()
     {
         $deprecations = array(

Tests/Loader/XmlFileLoaderTest.php

@@ -544,6 +544,7 @@ public function testAutowire()
 
     /**
      * @group legacy
+     * @requires function Symfony\Bridge\PhpUnit\ErrorAssert::assertDeprecationsAreTriggered
      */
     public function testAliasDefinitionContainsUnsupportedElements()
     {