Refs #6078, make sure pivot option does not display if table is not pivotted...

Refs #6078, make sure pivot option does not display if table is not pivotted and has no subtables (eg, when flattened).

core/Plugin/Visualization.php

@@ -297,6 +297,11 @@ class Visualization extends ViewDataTable
                 $this->config->report_last_updated_message = $this->makePrettyArchivedOnText();
             }
         }
+
+        $pivotBy = Common::getRequestVar('pivotBy', false) ?: $this->requestConfig->pivotBy;
+        if (empty($pivotBy)) {
+            $this->config->disablePivotBySubtableIfTableHasNoSubtables($this->dataTable);
+        }
     }
 
     private function applyFilters()

core/ViewDataTable/Config.php

@@ -9,6 +9,7 @@
 
 namespace Piwik\ViewDataTable;
 use Piwik\API\Request as ApiRequest;
+use Piwik\DataTable;
 use Piwik\DataTable\Filter\PivotByDimension;
 use Piwik\Metrics;
 use Piwik\Plugin\Report;
@@ -682,4 +683,15 @@ class Config
             }
         }
     }
+
+    public function disablePivotBySubtableIfTableHasNoSubtables(DataTable $table)
+    {
+        foreach ($table->getRows() as $row) {
+            if ($row->getIdSubDataTable() !== null) {
+                return;
+            }
+        }
+
+        $this->show_pivot_by_subtable = false;
+    }
 }