Make breadcrumb a heading for screen readers, fix #12885 (#13734)

* Make breadcrumb a heading for screen readers, fix #12885

* Use h2 in vis wizard step 2

src/core_plugins/kibana/public/context/app.html

@@ -1,7 +1,7 @@
 <div class="kuiLocalNav">
   <div class="kuiLocalNavRow">
     <div class="kuiLocalNavRow__section">
-      <div class="kuiLocalTitle">
+      <div class="kuiLocalTitle" role="heading" aria-level="1">
         Surrounding Documents in {{ contextApp.state.queryParameters.indexPatternId }}
       </div>
     </div>

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

@@ -23,6 +23,8 @@
         data-transclude-slot="topLeftCorner"
         class="kuiLocalBreadcrumbs"
         data-test-subj="breadcrumbs"
+        role="heading"
+        aria-level="1"
       >
         <div class="kuiLocalBreadcrumb">
           <a class="kuiLocalBreadcrumb__link" href="{{landingPageUrl()}}">Dashboard</a>

src/core_plugins/kibana/public/dashboard/listing/dashboard_listing.html

@@ -6,6 +6,8 @@
     <div
       data-transclude-slot="topLeftCorner"
       class="kuiLocalTitle"
+      role="heading"
+      aria-level="1"
     >
       Dashboard
     </div>

src/core_plugins/kibana/public/visualize/listing/visualize_listing.html

@@ -6,6 +6,8 @@
     <div
       data-transclude-slot="topLeftCorner"
       class="kuiLocalTitle"
+      role="heading"
+      aria-level="1"
     >
       Visualize
     </div>

src/core_plugins/kibana/public/visualize/wizard/step_2.html

@@ -15,9 +15,9 @@
 <div class="kuiViewContent kuiViewContent--constrainedWidth">
   <div class="wizard kuiViewContentItem">
     <div class="wizard-column wizard-column--small">
-      <h1 class="kuiTitle kuiVerticalRhythm">
+      <h2 class="kuiTitle kuiVerticalRhythm">
         From a New Search, Select Index
-      </h1>
+      </h2>
 
       <paginated-selectable-list
         per-page="20"

src/ui/public/kbn_top_nav/bread_crumbs/bread_crumbs.html

@@ -1,4 +1,9 @@
-<div class="kuiLocalBreadcrumbs" data-test-subj="breadcrumbs">
+<div
+  class="kuiLocalBreadcrumbs"
+  data-test-subj="breadcrumbs"
+  role="heading"
+  aria-level="1"
+>
   <div
     class="kuiLocalBreadcrumb"
     ng-if="useLinks"