Inline testing should pass arguments through json

If you are passing arguments like time objects that serialize to strings
but don't deserialize back automatically, inline testing was passing the
objects through raw meaning different behavior in tests vs. production.
Now the inline wrapper does a round trip through json.

lib/sidekiq/testing/inline.rb

@@ -29,7 +29,7 @@ module Sidekiq
     module ClassMethods
       alias_method :perform_async_old, :perform_async
       def perform_async(*args)
-        new.perform(*args)
+        new.perform(*Sidekiq.load_json(Sidekiq.dump_json(args)))
         true
       end
     end

test/test_testing_inline.rb

@@ -12,6 +12,7 @@ Sidekiq.hook_rails!
 class TestInline < MiniTest::Unit::TestCase
   describe 'sidekiq inline testing' do
     class InlineError < RuntimeError; end
+    class ParameterIsNotString < RuntimeError; end
 
     class InlineWorker
       include Sidekiq::Worker
@@ -20,6 +21,13 @@ class TestInline < MiniTest::Unit::TestCase
       end
     end
 
+    class InlineWorkerWithTimeParam
+      include Sidekiq::Worker
+      def perform(time)
+        raise ParameterIsNotString unless time.is_a?(String)
+      end
+    end
+
     class InlineFooMailer < ActionMailer::Base
       def bar(str)
         raise InlineError
@@ -71,5 +79,9 @@ class TestInline < MiniTest::Unit::TestCase
         Sidekiq::Client.enqueue(InlineWorker, false)
       end
     end
+
+    it 'should relay parameters through json' do
+      assert Sidekiq::Client.enqueue(InlineWorkerWithTimeParam, Time.now)
+    end
   end
 end