Removed cache backend option which explicitly set file permissions

[xtremeperf]

• Removed hashed_directory_umask option because it caused Cm_Cache_Backend_File class to explicitly set permissions using chmod, ignoring umask and setgid bit.
• Zend_Cache_Backend_File class deprecated and removed hashed_directory_umask option from Zend Framework v1.12+
• Magento Framework does not explicitly set file & directory permissions as of v2.0.6+

Description

This fix will allow the Magento Framework to no longer explicitly set file/directory permissions from the default cache backend by removing use of the hashed_directory_umask option
'hashed_directory_umask' => 0777,
from code within the file
lib/internal/Magento/Framework/App/Cache/Frontend/Factory.php.

This option was deprecated and removed from the Zend Framework as of version 1.12, but has remained in the Magento Framework.

Cm_Cache_Backend_File class still supports "hashed_directory_umask" option, with additional class code providing backwards compatibility with ZF 1.11.

However, setting this option was causing Cm_Cache_Backend_File to use PHP's chmod function recursively on the hashed directory structure during file and directory creation. Simply removing this option allows permissions to be inherited properly from the file system, and respects SETGID bit and Magento umask.

Fixed Issues (if relevant)

1. setup:di:compile's generated cache files inaccessible by the web-server user #11930: setup:di:compile's generated cache files inaccessible by the web-server user
2. Magento 2 Admin panel show loading on each page #10700: Magento 2 Admin panel show loading on each page

Manual testing scenarios

1. Install any version of Magento2
2. Check file & directory permissions from var/cache and var/page_cache and up
3. Notice that file & directory permissions are inherited from parent directories, and obey SETGID bit & umask.

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.

[orlangur]

Nice @xtremeperf! Glad to see this issue finally investigated and fixed, it was reported a bunch of times.

[magento-engcom-team]

Hi @orlangur, thank you for the review.
ENGCOM-1079 has been created to process this Pull Request

[magento-engcom-team]

@xtremeperf thank you for contributing. Please accept Community Contributors team invitation here to gain extended permissions for this repository.

[okorshenko]

@magento-engcom-team give me new test instance

[magento-engcom-team]

Hi @okorshenko, here is your new test Magento instance