Page meta title fix in case breadcrumb section is removed via XML

[latenights]

Description

Page meta title is visible only if breadcrumbs block is defined (not removed) in XML. If you remove it, page meta title disappears from category view and product view page.

Fixed Issues (if relevant)

1. SEO/HEAD - Meta title is null when breadcrumb section is removed via XML #4427:SEO/HEAD - Meta title is null when breadcrumb section is removed via XML

Manual testing scenarios

1. Remove breadcrumbs block in XML <referenceBlock name="breadcrumbs" remove="true"/>
2. Go to the category view or product view page
3. Check Page title in browser tab

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[magento-cicd2]

All committers have signed the CLA.

[magento-team]

@latenights thank you for your contribution to Magento 2 project

[maksek]

Hi @latenights, can you provide your email, so I can contact you regarding PR.

[latenights]

Hi @maksek , you can contact me at nudavmeste(at)nudavmeste.sk