MAGETWO-50794: SampleData is not applied correctly on regression environment

- fix unit test

Author: duhon

app/code/Magento/CatalogWidget/Test/Unit/Model/Rule/Condition/CombineTest.php

@@ -73,8 +73,13 @@ public function testGetNewChildSelectOptions()
     public function testCollectValidatedAttributes()
     {
         $collection = $this->getMockBuilder('\Magento\Catalog\Model\ResourceModel\Product\Collection')
-            ->disableOriginalConstructor()
+            ->disableOriginalConstructor()->setMethods(['getSelect'])
+            ->getMock();
+        $select = $this->getMockBuilder('\Magento\Framework\DB\Select')
+            ->disableOriginalConstructor()->setMethods(['getPart'])
             ->getMock();
+        $select->expects($this->any())->method('getPart')->with('from')->willReturn(['alias_table' => 'table_name']);
+        $collection->expects($this->any())->method('getSelect')->willReturn($select);
         $condition = $this->getMockBuilder('Magento\CatalogWidget\Model\Rule\Condition\Combine')
             ->disableOriginalConstructor()->setMethods(['addToCollection'])
             ->getMock();