Fix component kit rendering context (#971)

Closes #960

Author: joeldrapper

lib/phlex/kit.rb

@@ -63,8 +63,8 @@ def const_added(name)
 				end
 
 				define_singleton_method(name) do |*args, **kwargs, &block|
-					component, fiber_id = Thread.current[:__phlex_component__]
-					if (component && fiber_id == Fiber.current.object_id)
+					component = Thread.current[:__phlex_component__]
+					if component
 						component.instance_exec do
 							constant = me.const_get(name)
 							render(constant.new(*args, **kwargs), &block)

lib/phlex/sgml.rb

@@ -60,7 +60,8 @@ def internal_call(parent: nil, state: nil, &block)
 
 		block ||= @_content_block
 
-		Thread.current[:__phlex_component__] = [self, Fiber.current.object_id].freeze
+		previous_phlex_component = Thread.current[:__phlex_component__]
+		Thread.current[:__phlex_component__] = self
 
 		state.around_render(self) do
 			before_template(&block)
@@ -82,7 +83,7 @@ def internal_call(parent: nil, state: nil, &block)
 			after_template(&block)
 		end
 	ensure
-		Thread.current[:__phlex_component__] = [parent, Fiber.current.object_id].freeze
+		Thread.current[:__phlex_component__] = previous_phlex_component
 	end
 
 	def context