Modify z-index value in editor header

This value  was causing the header to stick in a strange way.

Change-Id: I5539e62cf1f17aeb82b45bdd2c46ae5323c073ff

polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.html

diff --git a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.html b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.html
index 10da09b..9038a18 100644
--- a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.html
+++ b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.html
@@ -38,7 +38,7 @@
       gr-fixed-panel {
         background-color: #fff;
         border-bottom: 1px #eee solid;
-        z-index: 10;
+        z-index: 1;
       }
       header,
       .subHeader {