Deprecate the P3P plugin and set it to disabled for new installations.
[Code Test]Implement tests for JLayout base
[x] JLayoutbase->setOptions() returns a JLayoutbase instance with empty parameter.
 [x] JLayoutbase->setOptions() returns a JLayoutbase instance with JRegistry parameter.
 [x] JLayoutbase->setOptions() returns a JLayoutbase instance with an array parameter.
 [x] JLayoutbase->getOptions() returns a JRegistry object when options parameter is empty.
 [x] JLayoutbase->getOptions() returns a JRegistry object when options parameter is an array.
 [x] JLayoutbase->getOptions() returns a JRegistry object when options parameter is a JRegistry object.
 [x] JLayoutbase->getOptions() returns a JRegistry object value using an array.
 [x] JLayoutbase->getOptions() returns a JRegistry object value using JRegistry.
 [x] JLayoutbase->resetOptions() and check options is empty.
 [x] Escaping special characters into html entities
 [x] Add one debug message to the queue
 [x] JLayoutBase->getDebugMessages() retrieves a list of debug messages in an array.
 [x] JLayoutBase->renderDebugMessages() returns string of messages separated by newline character.
 [x] JLayoutBase->render() returns an empty string.
Add Fixes suggested by Sebastian Bergmann
Merge pull request #1 from javigomez/jlayout-systemtests

Add Fixes suggested by Sebastian Bergmann
Merge pull request #4688 from Bakual/DeprecateP3P

Deprecate the P3P plugin and set it to disabled for new installations.
Don't access application class var directly
Merge pull request #4744 from wilsonge/patch-24

Don't access application class var directly
Merge pull request #4699 from roland-d/jlayout-systemtests

[Code Test] Implement tests for JLayout base
[fix] #4740 headers show when no record
Query fix in mod_articles_archive so it works in PostgreSQL. Fixes #3292
Modify JResponseJsonTest
Really fix it this time
Merge pull request #4749 from infograf768/usernotes

[fix] #4740 Users Notes: headers show when no record
Improvements to JSchemaChangesetTest
Merge branch 'staging' of github.com:joomla/joomla-cms into staging
Updating tests for JTable classes