Merge branch 'master' into postgres-query-builder

public/app/plugins/datasource/postgres/datasource.ts

@@ -123,25 +123,7 @@ export class PostgresDatasource {
   }
 
   testDatasource() {
-    return this.backendSrv
-      .datasourceRequest({
-        url: '/api/tsdb/query',
-        method: 'POST',
-        data: {
-          from: '5m',
-          to: 'now',
-          queries: [
-            {
-              refId: 'A',
-              intervalMs: 1,
-              maxDataPoints: 1,
-              datasourceId: this.id,
-              rawSql: 'SELECT 1',
-              format: 'table',
-            },
-          ],
-        },
-      })
+    return this.metricFindQuery('SELECT 1', {})
       .then(res => {
         return { status: 'success', message: 'Database Connection OK' };
       })