fix(table): fixes broken annotation rendering

closes #7268

public/app/plugins/panel/table/specs/transformers_specs.ts

@@ -153,14 +153,16 @@ describe('when transforming time series table', () => {
 
     describe('Annnotations', () => {
       var panel = {transform: 'annotations'};
-      var rawData = [
+      var rawData = {
+        annotations: [
           {
             min: 1000,
             text: 'hej',
             tags: ['tags', 'asd'],
             title: 'title',
           }
-      ];
+        ]
+      };
 
       beforeEach(() => {
         table = transformDataToTable(rawData, panel);

public/app/plugins/panel/table/transformers.ts

@@ -125,12 +125,12 @@ transformers['annotations'] = {
     model.columns.push({text: 'Text'});
     model.columns.push({text: 'Tags'});
 
-    if (!data || data.length === 0) {
+    if (!data || !data.annotations || data.annotations.length === 0) {
       return;
     }
 
-    for (var i = 0; i < data.length; i++) {
-      var evt = data[i];
+    for (var i = 0; i < data.annotations.length; i++) {
+      var evt = data.annotations[i];
       model.rows.push([evt.min, evt.title, evt.text, evt.tags]);
     }
   }