Merge forwardport of #12734 to 2.3-develop branch

Applied pull request patch https://github.com/magento/magento2/pull/12734.patch (created by @dzianis-yurevich) based on commit(s):
  1. e6a7a4e

Fixed GitHub Issues in 2.3-develop branch:
  - #6916: Update Bundle Product without changes in bundle items (reported by @magecodenet)

Author: magento-engcom-team

app/code/Magento/Bundle/Controller/Adminhtml/Product/Initialization/Helper/Plugin/Bundle.php

@@ -127,7 +127,7 @@ protected function processBundleOptionsData(\Magento\Catalog\Model\Product $prod
         }
         $options = [];
         foreach ($bundleOptionsData as $key => $optionData) {
-            if ((bool)$optionData['delete']) {
+            if (!empty($optionData['delete'])) {
                 continue;
             }
 

app/code/Magento/Bundle/Test/Unit/Controller/Adminhtml/Product/Initialization/Helper/Plugin/BundleTest.php

@@ -57,7 +57,10 @@ protected function setUp()
             'setOptions',
             'setCanSaveBundleSelections',
             '__wakeup',
-            'getOptionsReadonly'
+            'getOptionsReadonly',
+            'getBundleOptionsData',
+            'getExtensionAttributes',
+            'setExtensionAttributes',
         ];
         $this->productMock = $this->createPartialMock(\Magento\Catalog\Model\Product::class, $methods);
         $optionInterfaceFactory = $this->getMockBuilder(\Magento\Bundle\Api\Data\OptionInterfaceFactory::class)
@@ -127,6 +130,15 @@ public function testAfterInitializeIfBundleAnsCustomOptionsAndBundleSelectionsEx
         );
         $this->productMock->expects($this->once())->method('setOptions')->with(null);
         $this->productMock->expects($this->once())->method('setCanSaveBundleSelections')->with(true);
+        $this->productMock->expects($this->once())->method('getBundleOptionsData')->willReturn(['option_1' => ['delete' => 1]]);
+        $extentionAttribute = $this->getMockBuilder(\Magento\Catalog\Api\Data\ProductExtensionInterface::class)
+            ->disableOriginalConstructor()
+            ->setMethods(['setBundleProductOptions'])
+            ->getMockForAbstractClass();
+        $extentionAttribute->expects($this->once())->method('setBundleProductOptions')->with([]);
+        $this->productMock->expects($this->once())->method('getExtensionAttributes')->willReturn($extentionAttribute);
+        $this->productMock->expects($this->once())->method('setExtensionAttributes')->with($extentionAttribute);
+
         $this->model->afterInitialize($this->subjectMock, $this->productMock);
     }