It is not possible to add MS tile image meta via default_head_blocks.xml

lib/internal/Magento/Framework/View/Page/Config/Metadata/MsApplicationTileImage.php

@@ -0,0 +1,52 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\Framework\View\Page\Config\Metadata;
+
+use Magento\Framework\View\Asset\Repository as AssetRepository;
+
+/**
+ * Class MsApplicationTileImage
+ *
+ * Returns the URL for page `msapplication-TileImage` meta
+ */
+class MsApplicationTileImage
+{
+    /**#@+
+     * Constant of asset name
+     */
+    const META_NAME = 'msapplication-TileImage';
+
+    /**
+     * @var AssetRepository
+     */
+    private $assetRepo;
+
+    /**
+     * @param AssetRepository $assetRepo
+     */
+    public function __construct(AssetRepository $assetRepo)
+    {
+        $this->assetRepo = $assetRepo;
+    }
+
+    /**
+     * Get asset URL from given metadata content
+     *
+     * @param string $content
+     *
+     * @return string
+     */
+    public function getUrl(string $content): string
+    {
+        if (!parse_url($content, PHP_URL_SCHEME)) {
+            return $this->assetRepo->getUrl($content);
+        }
+
+        return $content;
+    }
+}

lib/internal/Magento/Framework/View/Page/Config/Renderer.php

@@ -9,6 +9,7 @@
 use Magento\Framework\Exception\LocalizedException;
 use Magento\Framework\View\Asset\GroupedCollection;
 use Magento\Framework\View\Page\Config;
+use Magento\Framework\View\Page\Config\Metadata\MsApplicationTileImage;
 
 /**
  * Page config Renderer model
@@ -74,28 +75,37 @@ class Renderer implements RendererInterface
      */
     protected $urlBuilder;
 
+    /**
+     * @var MsApplicationTileImage
+     */
+    private $msApplicationTileImage;
+
     /**
      * @param Config $pageConfig
      * @param \Magento\Framework\View\Asset\MergeService $assetMergeService
      * @param \Magento\Framework\UrlInterface $urlBuilder
      * @param \Magento\Framework\Escaper $escaper
      * @param \Magento\Framework\Stdlib\StringUtils $string
      * @param \Psr\Log\LoggerInterface $logger
+     * @param MsApplicationTileImage|null $msApplicationTileImage
      */
     public function __construct(
         Config $pageConfig,
         \Magento\Framework\View\Asset\MergeService $assetMergeService,
         \Magento\Framework\UrlInterface $urlBuilder,
         \Magento\Framework\Escaper $escaper,
         \Magento\Framework\Stdlib\StringUtils $string,
-        \Psr\Log\LoggerInterface $logger
+        \Psr\Log\LoggerInterface $logger,
+        MsApplicationTileImage $msApplicationTileImage = null
     ) {
         $this->pageConfig = $pageConfig;
         $this->assetMergeService = $assetMergeService;
         $this->urlBuilder = $urlBuilder;
         $this->escaper = $escaper;
         $this->string = $string;
         $this->logger = $logger;
+        $this->msApplicationTileImage = $msApplicationTileImage ?:
+            \Magento\Framework\App\ObjectManager::getInstance()->get(MsApplicationTileImage::class);
     }
 
     /**
@@ -179,6 +189,10 @@ protected function processMetadataContent($name, $content)
         if (method_exists($this->pageConfig, $method)) {
             $content = $this->pageConfig->$method();
         }
+        if ($content && $name === $this->msApplicationTileImage::META_NAME) {
+            $content = $this->msApplicationTileImage->getUrl($content);
+        }
+
         return $content;
     }
 

lib/internal/Magento/Framework/View/Test/Unit/Page/Config/RendererTest.php

@@ -8,6 +8,7 @@
 
 use Magento\Framework\TestFramework\Unit\Helper\ObjectManager;
 use Magento\Framework\View\Asset\GroupedCollection;
+use Magento\Framework\View\Page\Config\Metadata\MsApplicationTileImage;
 use Magento\Framework\View\Page\Config\Renderer;
 use Magento\Framework\View\Page\Config\Generator;
 
@@ -58,6 +59,11 @@ class RendererTest extends \PHPUnit\Framework\TestCase
      */
     protected $loggerMock;
 
+    /**
+     * @var MsApplicationTileImage|\PHPUnit_Framework_MockObject_MockObject
+     */
+    protected $msApplicationTileImageMock;
+
     /**
      * @var \Magento\Framework\View\Asset\GroupedCollection|\PHPUnit_Framework_MockObject_MockObject
      */
@@ -99,6 +105,10 @@ protected function setUp()
         $this->loggerMock = $this->getMockBuilder(\Psr\Log\LoggerInterface::class)
             ->getMock();
 
+        $this->msApplicationTileImageMock = $this->getMockBuilder(MsApplicationTileImage::class)
+            ->disableOriginalConstructor()
+            ->getMock();
+
         $this->assetsCollection = $this->getMockBuilder(\Magento\Framework\View\Asset\GroupedCollection::class)
             ->setMethods(['getGroups'])
             ->disableOriginalConstructor()
@@ -120,7 +130,8 @@ protected function setUp()
                 'urlBuilder' => $this->urlBuilderMock,
                 'escaper' => $this->escaperMock,
                 'string' => $this->stringMock,
-                'logger' => $this->loggerMock
+                'logger' => $this->loggerMock,
+                'msApplicationTileImage' => $this->msApplicationTileImageMock
             ]
         );
     }
@@ -147,15 +158,17 @@ public function testRenderMetadata()
             'content_type' => 'content_type_value',
             'x_ua_compatible' => 'x_ua_compatible_value',
             'media_type' => 'media_type_value',
-            'og:video:secure_url' => 'secure_url'
+            'og:video:secure_url' => 'secure_url',
+            'msapplication-TileImage' => 'https://site.domain/ms-tile.jpg'
         ];
         $metadataValueCharset = 'newCharsetValue';
 
         $expected = '<meta charset="newCharsetValue"/>' . "\n"
             . '<meta name="metadataName" content="metadataValue"/>' . "\n"
             . '<meta http-equiv="Content-Type" content="content_type_value"/>' . "\n"
             . '<meta http-equiv="X-UA-Compatible" content="x_ua_compatible_value"/>' . "\n"
-            . '<meta property="og:video:secure_url" content="secure_url"/>' . "\n";
+            . '<meta property="og:video:secure_url" content="secure_url"/>' . "\n"
+            . '<meta name="msapplication-TileImage" content="https://site.domain/ms-tile.jpg"/>' . "\n";
 
         $this->stringMock->expects($this->at(0))
             ->method('upperCaseWords')
@@ -171,6 +184,37 @@ public function testRenderMetadata()
             ->method('getMetadata')
             ->will($this->returnValue($metadata));
 
+        $this->msApplicationTileImageMock
+            ->expects($this->once())
+            ->method('getUrl')
+            ->with('https://site.domain/ms-tile.jpg')
+            ->will($this->returnValue('https://site.domain/ms-tile.jpg'));
+
+        $this->assertEquals($expected, $this->renderer->renderMetadata());
+    }
+
+    /**
+     * Test renderMetadata when it has 'msapplication-TileImage' meta passed
+     */
+    public function testRenderMetadataWithMsApplicationTileImageAsset()
+    {
+        $metadata = [
+            'msapplication-TileImage' => 'images/ms-tile.jpg'
+        ];
+        $expectedMetaUrl = 'https://site.domain/images/ms-tile.jpg';
+        $expected = '<meta name="msapplication-TileImage" content="' . $expectedMetaUrl . '"/>' . "\n";
+
+        $this->pageConfigMock
+            ->expects($this->once())
+            ->method('getMetadata')
+            ->will($this->returnValue($metadata));
+
+        $this->msApplicationTileImageMock
+            ->expects($this->once())
+            ->method('getUrl')
+            ->with('images/ms-tile.jpg')
+            ->will($this->returnValue($expectedMetaUrl));
+
         $this->assertEquals($expected, $this->renderer->renderMetadata());
     }
 
@@ -277,12 +321,14 @@ public function testRenderAssets($groupOne, $groupTwo, $expectedResult)
             ->willReturn($groupAssetsOne);
         $groupMockOne->expects($this->any())
             ->method('getProperty')
-            ->willReturnMap([
-                [GroupedCollection::PROPERTY_CAN_MERGE, true],
-                [GroupedCollection::PROPERTY_CONTENT_TYPE, $groupOne['type']],
-                ['attributes', $groupOne['attributes']],
-                ['ie_condition', $groupOne['condition']],
-            ]);
+            ->willReturnMap(
+                [
+                    [GroupedCollection::PROPERTY_CAN_MERGE, true],
+                    [GroupedCollection::PROPERTY_CONTENT_TYPE, $groupOne['type']],
+                    ['attributes', $groupOne['attributes']],
+                    ['ie_condition', $groupOne['condition']],
+                ]
+            );
 
         $assetMockTwo = $this->createMock(\Magento\Framework\View\Asset\AssetInterface::class);
         $assetMockTwo->expects($this->once())
@@ -300,12 +346,14 @@ public function testRenderAssets($groupOne, $groupTwo, $expectedResult)
             ->willReturn($groupAssetsTwo);
         $groupMockTwo->expects($this->any())
             ->method('getProperty')
-            ->willReturnMap([
-                [GroupedCollection::PROPERTY_CAN_MERGE, true],
-                [GroupedCollection::PROPERTY_CONTENT_TYPE, $groupTwo['type']],
-                ['attributes', $groupTwo['attributes']],
-                ['ie_condition', $groupTwo['condition']],
-            ]);
+            ->willReturnMap(
+                [
+                    [GroupedCollection::PROPERTY_CAN_MERGE, true],
+                    [GroupedCollection::PROPERTY_CONTENT_TYPE, $groupTwo['type']],
+                    ['attributes', $groupTwo['attributes']],
+                    ['ie_condition', $groupTwo['condition']],
+                ]
+            );
 
         $this->pageConfigMock->expects($this->once())
             ->method('getAssetCollection')