Graph: show range warning when all data is outside time range (#27603)

public/app/plugins/panel/graph/module.ts

@@ -271,12 +271,14 @@ export class GraphCtrl extends MetricsPanelCtrl {
       };
     }
 
-    // Look for data points outside time range
+    // If any data is in range, do not return an error
     for (const series of this.seriesList) {
       if (!series.isOutsideRange) {
-        continue;
+        return undefined;
+      }
     }
 
+    // All data is outside the time range
     const dataWarning: DataWarning = {
       title: 'Data outside time range',
       tip: 'Can be caused by timezone mismatch or missing time filter in query',
@@ -299,8 +301,6 @@ export class GraphCtrl extends MetricsPanelCtrl {
 
     return dataWarning;
   }
-    return undefined;
-  }
 
   onRender() {
     if (!this.seriesList) {