core: get rid of dependencies on @env from mixin

lib/vagrant/action/builtin/mixin_provisioners.rb

@@ -6,17 +6,17 @@ module Vagrant
         # This is safe to call multiple times since it will cache the results.
         #
         # @return [Array<Provisioner>]
-        def provisioner_instances
+        def provisioner_instances(env)
           return @_provisioner_instances if @_provisioner_instances
 
           # Make the mapping that'll keep track of provisioner => type
           @_provisioner_types = {}
 
           # Get all the configured provisioners
-          @_provisioner_instances = @env[:machine].config.vm.provisioners.map do |provisioner|
+          @_provisioner_instances = env[:machine].config.vm.provisioners.map do |provisioner|
             # Instantiate the provisioner
             klass  = Vagrant.plugin("2").manager.provisioners[provisioner.name]
-            result = klass.new(@env[:machine], provisioner.config)
+            result = klass.new(env[:machine], provisioner.config)
 
             # Store in the type map so that --provision-with works properly
             @_provisioner_types[result] = provisioner.name

lib/vagrant/action/builtin/provision.rb

@@ -51,7 +51,7 @@ module Vagrant
           end
 
           # Ask the provisioners to modify the configuration if needed
-          provisioner_instances.each do |p|
+          provisioner_instances(env).each do |p|
             p.configure(env[:machine].config)
           end
 
@@ -60,7 +60,7 @@ module Vagrant
 
           # Actually provision if we enabled it
           if enabled
-            provisioner_instances.each do |p|
+            provisioner_instances(env).each do |p|
               next if env[:provision_types] && \
                 !env[:provision_types].include?(provisioner_type_map[p])
 

lib/vagrant/action/builtin/provisioner_cleanup.rb

@@ -28,7 +28,7 @@ module Vagrant
 
         def do_cleanup(env)
           # Ask the provisioners to modify the configuration if needed
-          provisioner_instances.each do |p|
+          provisioner_instances(env).each do |p|
             env[:ui].info(I18n.t(
               "vagrant.provisioner_cleanup",
               name: provisioner_type_map[p].to_s))