Fix mr tabs position

app/assets/stylesheets/pages/diff.scss

@@ -578,12 +578,12 @@
   @media (min-width: $screen-sm-min) {
     position: -webkit-sticky;
     position: sticky;
-    top: 34px;
+    top: 24px;
     background-color: $white-light;
     z-index: 190;
 
     &.diff-files-changed-merge-request {
-      top: 84px;
+      top: 76px;
     }
 
     + .files,
@@ -614,6 +614,14 @@
   }
 }
 
+@media (min-width: $screen-sm-min) {
+  .with-performance-bar {
+    .diff-files-changed.diff-files-changed-merge-request {
+      top: 76px + $performance-bar-height;
+    }
+  }
+}
+
 .diff-file-changes {
   width: 450px;
   z-index: 150;

app/assets/stylesheets/pages/issuable.scss

@@ -220,7 +220,7 @@
 
 .right-sidebar {
   position: absolute;
-  top: $header-height;
+  top: $new-navbar-height;
   bottom: 0;
   right: 0;
   transition: width .3s;
@@ -230,7 +230,7 @@
 
   .issuable-sidebar {
     width: calc(100% + 100px);
-    height: calc(100% - #{$header-height});
+    height: calc(100% - #{$new-navbar-height});
     overflow-y: scroll;
     overflow-x: hidden;
     -webkit-overflow-scrolling: touch;
@@ -479,10 +479,10 @@
 }
 
 .with-performance-bar .right-sidebar {
-  top: $header-height + $performance-bar-height;
+  top: $new-navbar-height + $performance-bar-height;
 
   .issuable-sidebar {
-    height: calc(100% - #{$header-height} - #{$performance-bar-height});
+    height: calc(100% - #{$new-navbar-height} - #{$performance-bar-height});
   }
 }
 

app/assets/stylesheets/pages/merge_requests.scss

@@ -645,7 +645,7 @@
 }
 
 .merge-request-tabs-holder {
-  top: $header-height;
+  top: $new-navbar-height;
   z-index: 200;
   background-color: $white-light;
   border-bottom: 1px solid $border-color;
@@ -675,7 +675,7 @@
 }
 
 .with-performance-bar .merge-request-tabs-holder {
-  top: $header-height + $performance-bar-height;
+  top: $new-navbar-height + $performance-bar-height;
 }
 
 .merge-request-tabs {