Add to the matrix of Travis tests an entry that runs the Active Support
tests when `ActiveSupport.to_time_preserves_timezone = true`.

This reverts commit 2f52f969.

Conflicts:
	actionmailer/test/abstract_unit.rb
	actionview/test/abstract_unit.rb
	activemodel/test/cases/helper.rb
	activerecord/test/cases/helper.rb
	activesupport/test/abstract_unit.rb
	railties/test/abstract_unit.rb

Goals:

1. Default to :random for newly generated applications
2. Default to :sorted for existing applications with a warning
3. Only show the warning once
4. Only show the warning if the app actually uses AS::TestCase

Fixes #16769

We're seeing too many failures to believe otherwise.

This reverts commits bc116a55,
cbde413d,
bf0a6793, and
2440933f.

Calling ActiveSupport::TestCase.i_suck_and_my_tests_are_order_dependent! in AS::TestCase makes
everyone's tests order dependent, which should never be done by the framework.

We are planning to remove mocha from our test suite because of
performance problems. To make this possible we should stop require mocha
on ActionSupport::TestCase.

This should not affect applications since users still need to add mocha
to Gemfile and this already load mocha.

Added FIXME notes to place that still need mocha removal

This Adds helpers(jruby_skip & rbx_skip). In Future, Plan is to use
these helpers instead of calls directly to
RUBY_ENGINE/RbConfig/JRUBY_VERSION

File 'empty_bool.rb' was introduced around 4 years ago in
c10958fb to remove method redefined
warning in AS test suite, however we do not have such need for reuse
anymore, so we can safely move the constants back to the file where
they are currently used and get rid of the extra file/require.

core extensions (`core_ext/string/encoding`).

this would give us some more clues in case a test silently dies inside Thread

minitest/autorun load minitest/spec polluting the global namespace with
the DSL that we don't want on Rails

memcache-client was deprecated in favour of dalli in 2010.

Mocha is already required by AS::TestCase, so remove the duplicate
requires.

There are a bunch of other implicit branches that adds
1.8.x specific code that still needs to be removed. Pull
requests for those cases are welcome.

As of this writing the JRuby client does not support a default port.
Signed-off-by: NXavier Noria <fxn@hashref.com>

defines ORIG_ARGV in Active Support's abstract_unit.rb (used in isolation.rb) [#4922 state:resolved]
Signed-off-by: NXavier Noria <fxn@hashref.com>

Signed-off-by: NJeremy Kemper <jeremy@bitsweat.net>

This reverts commit eec2d301.

This commit broke tests. You cannot have a file called "bundler" on the load path.