Update to drupal 8.0.0-rc1. For more information, see https://www.drupal.org/node/2582663

vendor/doctrine/cache/tests/travis/php.ini

@@ -0,0 +1,7 @@
+extension="mongo.so"
+extension="memcache.so"
+extension="memcached.so"
+extension="redis.so"
+
+apc.enabled=1
+apc.enable_cli=1

vendor/doctrine/cache/tests/travis/phpunit.travis.xml

@@ -0,0 +1,35 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit bootstrap="../Doctrine/Tests/TestInit.php"
+        convertWarningsToExceptions="true"
+        convertNoticesToExceptions="true"
+        convertErrorsToExceptions="true"
+        backupStaticAttributes="false"
+        processIsolation="false"
+        stopOnFailure="false"
+        backupGlobals="false"
+        syntaxCheck="false"
+        colors="true">
+
+    <logging>
+        <log type="coverage-clover" target="../../build/logs/clover.xml"/>
+    </logging>
+
+    <testsuites>
+        <testsuite name="Doctrine Cache Test Suite">
+            <directory>../Doctrine/</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+        <whitelist>
+            <directory>../../lib/Doctrine/</directory>
+        </whitelist>
+    </filter>
+    
+    <groups>
+        <exclude>
+            <group>performance</group>
+        </exclude>
+    </groups>
+</phpunit>