Merge remote-tracking branch 'origin/MAGETWO-36143' into develop

Author: Roman Ganin

app/code/Magento/Reports/Model/Resource/Report/Collection.php

@@ -174,7 +174,7 @@ protected function _getDayInterval(\DateTime $dateStart)
                 \IntlDateFormatter::SHORT,
                 \IntlDateFormatter::NONE
             ),
-            'start' => $dateStart->format('Y-m-d H:i:s'),
+            'start' => $dateStart->format('Y-m-d 00:00:00'),
             'end' => $dateStart->format('Y-m-d 23:59:59'),
         ];
         return $interval;