Issue #2857378 by bojanz, vasike, mglaman: Hide order activity when empty

[vasike]

[mglaman]

phpcs issues

The command "phpcs --standard=phpcs.xml src -s" exited with 0.
7.39s$ phpcs --standard=phpcs.xml modules -s
FILE: ...erce/modules/log/tests/src/Functional/OrderAdminActivityTest.php
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FOUND 3 ERRORS AFFECTING 3 LINES
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 17 | ERROR | [x] Do not append variable name "$order" to the type
    |       |     declaration in a member variable comment
    |       |     (Drupal.Commenting.VariableComment.InlineVariableName)
 68 | ERROR | [x] Expected 1 blank line after function; 0 found
    |       |     (Squiz.WhiteSpace.FunctionSpacing.After)
 69 | ERROR | [x] The closing brace for the class must have an empty line
    |       |     before it
    |       |     (Drupal.Classes.ClassDeclaration.CloseBraceAfterBody)
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PHPCBF CAN FIX THE 3 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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[vasike]

it seems this fails because of this https://github.com/drupalcommerce/commerce/pull/711 issue: https://www.drupal.org/node/2867430