ENGCOM-3559: Unit tests fix.

Author: p-bystritsky

app/code/Magento/Quote/Test/Unit/Model/Quote/Item/UpdaterTest.php

@@ -67,7 +67,7 @@ protected function setUp()
                 'addOption',
                 'setCustomPrice',
                 'setOriginalCustomPrice',
-                'unsetData',
+            'setData',
                 'hasData',
                 'setIsQtyDecimal'
             ]);
@@ -353,7 +353,11 @@ public function testUpdateUnsetCustomPrice()
             ->will($this->returnValue($buyRequestMock));
 
         $this->itemMock->expects($this->exactly(2))
-            ->method('unsetData');
+            ->method('setData')
+            ->withConsecutive(
+                ['custom_price', null],
+                ['original_custom_price', null]
+            );
 
         $this->itemMock->expects($this->once())
             ->method('hasData')