Rely on NoMethodError#name when deciding to raise DelegationError.

Different Ruby implementations present backtraces differently, as
it should be an information consumed by humans.
A better implementation should use data from the error, in this case
returned by NoMethodError#name.

Fixes issues with Rubinius, which presents backtraces differently from
MRI.
Skip few of the ActiveSupport'sinflector test on JRuby
Escape the message of an exception in debug_exceptions to avoid bad rendering
Merge pull request #11961 from Intrepidd/debug-exception-html

Escape the message of an exception in debug_exceptions to avoid bad rendering
Added method to skip tests on Rubinius to AS/abstract_unit.
Skip tests involving $SAFE, it's not supported on Rubinius.
Merge pull request #11959 from razielgn/skip-global-safe-tests-on-rubinius

Skip tests involving $SAFE on Rubinius, it's not supported.
Merge pull request #11850 from razielgn/mod-delegation-backtrace

Generalize backtrace check on DelegationError.
Define jruby_skip to skip test on JRuby
Merge pull request #11932 from gaurish/skip-encoding-convertor

[JRuby] Skip few of the ActiveSupport's inflector test cases

Conflicts:
	activesupport/test/abstract_unit.rb