core: pass environment into all host caps

lib/vagrant/environment.rb

@@ -498,7 +498,8 @@ module Vagrant
         @host = Host.new(
           host_klass,
           Vagrant.plugin("2").manager.hosts,
-          Vagrant.plugin("2").manager.host_capabilities)
+          Vagrant.plugin("2").manager.host_capabilities,
+          self)
       rescue Errors::CapabilityHostNotDetected
         # If the auto-detect failed, then we create a brand new host
         # with no capabilities and use that. This should almost never happen
@@ -510,7 +511,7 @@ module Vagrant
         hosts     = { generic: [klass, nil] }
         host_caps = {}
 
-        @host = Host.new(:generic, hosts, host_caps)
+        @host = Host.new(:generic, hosts, host_caps, self)
       rescue Errors::CapabilityHostExplicitNotDetected => e
         raise Errors::HostExplicitNotDetected, e.extra_data
       end

lib/vagrant/host.rb

@@ -9,8 +9,8 @@ module Vagrant
   class Host
     include CapabilityHost
 
-    def initialize(host, hosts, capabilities)
-      initialize_capabilities!(host, hosts, capabilities)
+    def initialize(host, hosts, capabilities, env)
+      initialize_capabilities!(host, hosts, capabilities, env)
     end
   end
 end

test/unit/vagrant/host_test.rb

@@ -7,11 +7,12 @@ describe Vagrant::Host do
 
   let(:capabilities) { {} }
   let(:hosts)  { {} }
+  let(:env) { Object.new }
 
   it "initializes the capabilities" do
     described_class.any_instance.should_receive(:initialize_capabilities!).
-      with(:foo, hosts, capabilities)
+      with(:foo, hosts, capabilities, env)
 
-    described_class.new(:foo, hosts, capabilities)
+    described_class.new(:foo, hosts, capabilities, env)
   end
 end