[Installer] Adding sandbox to PostInstallHooksContext

lib/cocoapods/installer/post_install_hooks_context.rb

@@ -12,6 +12,10 @@ module Pod
       #
       attr_accessor :pods_project
 
+      # @return [Sandbox] The Sandbox for the project.
+      #
+      attr_accessor :sandbox
+
       # @return [Array<UmbrellaTargetDescription>] The list of
       #         the CocoaPods umbrella targets generated by the installer.
       #
@@ -45,6 +49,7 @@ module Pod
         result = new
         result.sandbox_root = sandbox.root.to_s
         result.pods_project = sandbox.project
+        result.sandbox = sandbox
         result.umbrella_targets = umbrella_targets_descriptions
         result
       end

spec/unit/installer/post_install_hooks_context_spec.rb

@@ -20,6 +20,7 @@ module Pod
       result.class.should == Installer::PostInstallHooksContext
       result.sandbox_root.should == '/path'
       result.pods_project.should == pods_project
+      result.sandbox.should == sandbox
       result.umbrella_targets.count.should == 1
       umbrella_target = result.umbrella_targets.first
       umbrella_target.user_target_uuids.should == ['UUID']