Expose the exception which triggers recovery methods through the "vagrant.error" environmental hash

lib/vagrant/action/warden.rb

@@ -23,7 +23,9 @@ module Vagrant
           raise Errors::VagrantInterrupt.new if env.interrupted?
           @stack.unshift(@actions.shift).first.call(env)
           raise Errors::VagrantInterrupt.new if env.interrupted?
-        rescue
+        rescue Exception => e
+          env["vagrant.error"] = e
+
           # Something went horribly wrong. Start the rescue chain then
           # reraise the exception to properly kick us out of limbo here.
           begin_rescue(env)

test/vagrant/action/warden_test.rb

@@ -63,7 +63,10 @@ class ActionWardenTest < Test::Unit::TestCase
       end
 
       @instance.actions << Foo.new
-      @instance.expects(:begin_rescue)
+      @instance.expects(:begin_rescue).with() do |env|
+        assert env["vagrant.error"].is_a?(RuntimeError)
+        true
+      end
       assert_raises(RuntimeError) { @instance.call(new_env) }
     end