[5.x] Remove expanded panel mode due to performance issue [forward port] (#10015)

* [5.x] Remove expanded panel mode due to performance issue [forward port]

Forward port of https://github.com/elastic/kibana/pull/10010

* remove release notes section with expanded panel

docs/release-notes/5.2.0.asciidoc

@@ -12,8 +12,6 @@ Core::
 * Support for searching against tribe nodes {pull}9132[#9132]
 * Automatically select default index pattern if there is only one {pull}9679[#9679]
 * Remove "will be cached for next time" message from loading screen {pull}9383[#9383]
-Dashboard::
-* Individual dashboard panels can now be temporarily expanded to fit the entire dashboard {pull}9666[#9666]
 Discover::
 * Improved consistency with the sidebar interface {pull}7958[#7958]
 Saved Objects::

src/core_plugins/kibana/public/dashboard/panel/panel.html

@@ -4,9 +4,12 @@
       {{::savedObj.title}}
     </span>
     <div class="btn-group">
+      <!--
+      Pulling out due to https://github.com/elastic/kibana/issues/9766.  Uncomment when fixed.
       <a aria-label="Expand" ng-click="toggleExpand()">
         <span class="fa" ng-class="{'fa-expand': !isExpanded, 'fa-compress': isExpanded}"></span>
       </a>
+      -->
       <a aria-label="Edit" ng-show="!isFullScreenMode && editUrl" ng-href="{{::editUrl}}">
         <i aria-hidden="true" class="fa fa-pencil"></i>
       </a>