Remove 1.8 compatible code
Merge pull request #12280 from kennyj/remove_1_8_compat

Remove 1.8 compatible code
Fix incorrect assert_redirected_to failure message

In some instances, `assert_redirected_to` assertion was returning an
incorrect and misleading failure message when the assertion failed.
This was due to a disconnect in how the assertion computes the redirect
string for the failure message and how `redirect_to` computes the
string that is actually used for redirection.

I made the `_compute_redirect_to_loaction` method used by `redirect_to`
public and call that from the method `assert_redirect_to` uses to
calculate the URL.

The reveals a new test failure due to the regex used by
`_compute_redirect_to_location` allow `_` in the URL scheme.
Fix regex used to find URI schemes in redirect_to

The previous regex was allowing `_` in the URI scheme, which is not
allowed by RFC 3986. This change brings the regex in line with the RFC.
Merge pull request #10362 from derekprior/dp-fix-assert-redirect-to

Fix incorrect assert_redirected_to failure message
Run Tests against JRuby master

Many of the failing tests in rails test suite fail because of missing encoding support, example #11739


And according to recent announcement, lot of encoding issues have been fixed in current master.  http://ruby.11.x6.nabble.com/Big-encoding-patches-landed-on-master-td4993719.html


So lets test against JRuby master & incase there are still bugs. it would be easier to report them to JRuby.
Merge pull request #12294 from gaurish/patch-1

Run Tests against JRuby master
Allow failures in jruby-head
Merge pull request #12295 from gaurish/patch-2

Allow failures in jruby-head
mention controller test base class in testing guide. [ci skip]