move milestone due date info to sidebar

app/assets/stylesheets/pages/milestone.scss

@@ -62,10 +62,6 @@
     }
   }
-  .remaining-days {
-    color: $orange-600;
-  }
-
   .milestone-stats-and-buttons {
     display: flex;
     justify-content: flex-start;

app/views/projects/milestones/show.html.haml

@@ -58,4 +58,4 @@
   = render 'shared/milestones/summary', milestone: @milestone, project: @project
   = render 'shared/milestones/tabs', milestone: @milestone
-  = render 'shared/milestones/sidebar', milestone: @milestone, affix_offset: 153
+  = render 'shared/milestones/sidebar', milestone: @milestone, project: @project, affix_offset: 153

app/views/shared/milestones/_sidebar.html.haml

 - affix_offset = local_assigns.fetch(:affix_offset, "102")
+- project = local_assigns[:project]
 %aside.right-sidebar.js-right-sidebar{ data: { "offset-top" => affix_offset, "spy" => "affix" }, class: sidebar_gutter_collapsed_class, 'aria-live' => 'polite' }
   .issuable-sidebar
@@ -9,6 +10,27 @@
       %span.issuable-header-text.hide-collapsed
         Milestone #{milestone.try(:to_reference) || milestone.title}
+    - if project
+      .block.due_date
+        .sidebar-collapsed-icon
+          = icon('calendar', 'aria-hidden': 'true')
+          %span.js-due-date-sidebar-value
+            = milestone.due_date.try(:to_s, :medium) || 'None'
+        .title.hide-collapsed
+          Due date
+          - if can?(current_user, :admin_milestone, @project)
+            = link_to 'Edit', edit_namespace_project_milestone_path(@project.namespace, @project, @milestone), class: 'edit-link pull-right'
+        .value.hide-collapsed
+          %span.value-content
+            - if milestone.due_date
+              %span.bold= milestone.due_date.to_s(:medium)
+            - else
+              %span.no-value No due date
+          - remaining_days = milestone_remaining_days(milestone)
+          - if remaining_days.present?
+            = surround '(', ')' do
+              %span.remaining-days= remaining_days
+
     - milestone_ref = milestone.try(:to_reference, full: true)
     - if milestone_ref.present?
       .block

app/views/shared/milestones/_summary.html.haml

@@ -26,10 +26,6 @@
         %span.milestone-stat
           %strong== #{milestone.percent_complete(current_user)}%
           complete
-        - remaining_days = milestone_remaining_days(milestone)
-        - if remaining_days.present?
-          %span.milestone-stat
-            %span.remaining-days= remaining_days
       .milestone-progress-buttons
         %span.tab-issues-buttons