[Backport 2.3] #12625: Add Current Date to update_time Field for Block and Pages

[osrecio]

Set Current Date Time to update_time field

Description

add current date time to 'update_time' in _beforeSave method for Page and Block

Fixed Issues (if relevant)

1. when saving a page in magento 2.2.1, 'Modified' date field is not getting updated #12625: when saving a page in magento 2.2.1, 'Modified' date field is not getting updated

Manual testing scenarios

1. Login to magento admin
2. Go to Content > Pages
3. In Action column, click select > edit
4. Make changes to that page and click 'Save Page'

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)

[dmanners]

This is a backport of #12636

[sidolov]

Please, use framework implementation for date value \Magento\Framework\Stdlib\DateTime\DateTime::date

[osrecio]

@sidolov Changes made, and added integration tests for Cms Block 😃

[sidolov]

Hi @osrecio , i investigated this issue deeper and find that field 'update_time' should be automatically updated by Mysql engine. In db this field has type timestamp and must be automatically updated after row has been changed. We had the same issue with quote (bf9ea28).
This behavior fixing by unset 'update_time' field before model save:

if ($this->hasDataChanges()) {
    $this->unsUpdateTime();
}

[osrecio]

Hi @sidolov I changed Models to add in method beforeSave:

if ($this->hasDataChanges()) {
    $this->unsUpdateTime();
}

Thanks for catch it, I made my life complicated changing Resource Model :)