Resolve "Modify the empty state of changes in MR"

app/assets/stylesheets/framework/blocks.scss

@@ -10,7 +10,6 @@
   color: $gl-text-color;
   font-weight: $gl-font-weight-normal;
   font-size: 14px;
-  line-height: 36px;
 
   &.diff-collapsed {
     padding: 5px;

app/views/projects/merge_requests/diffs/_diffs.html.haml

@@ -4,14 +4,17 @@
 = render 'projects/merge_requests/diffs/commit_widget'
 
 - if @merge_request_diff&.empty?
-  .nothing-here-block
-    = image_tag 'illustrations/merge_request_changes_empty.svg'
-    = succeed '.' do
-      No changes between
-      %span.ref-name= @merge_request.source_branch
-      and
-      %span.ref-name= @merge_request.target_branch
-      %p= link_to 'Create commit', project_new_blob_path(@project, @merge_request.source_branch), class: 'btn btn-save'
+  .row.empty-state.nothing-here-block
+    .col-xs-12
+      .svg-content= image_tag 'illustrations/merge_request_changes_empty.svg'
+    .col-xs-12
+      .text-content.text-center
+        %p
+          No changes between
+          %span.ref-name= @merge_request.source_branch
+          and
+          %span.ref-name= @merge_request.target_branch
+          .text-center= link_to 'Create commit', project_new_blob_path(@project, @merge_request.source_branch), class: 'btn btn-save'
 - else
   - diff_viewable = @merge_request_diff ? @merge_request_diff.collected? || @merge_request_diff.overflow? : true
   - if diff_viewable