Fixing null printed in UI

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@177957 a5903396-d722-0410-b921-86c7d4935375
Implemented chaining pattern for CarbonTomcatValves


git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@177959 a5903396-d722-0410-b921-86c7d4935375