The primary text in Granite.HeaderLabel misaligned when placed in Gtk.Popover

[ryonakano]

What Happened?

The primary and secondary text in Granite.HeaderLabel are aligned to the start if it's placed in Gtk.Box.
However, the primary text is not aligned to the start if the label is placed in Gtk.Popover.

Steps to Reproduce

1. Clone, compile, and run the following demo app: https://github.com/ryonakano/junk/tree/headerlabel-test
2. Click the "Open Popover" button to see the style differences between Granite.HeaderLabel in Gtk.Box and Granite.HeaderLabel in Gtk.Popover

Expected Behavior

The primary and secondary text in Granite.HeaderLabel should be aligned to the start, regardless of the widget where it is placed.

OS Version

7.x (Horus)

Software Version

Latest release (I have run all updates)

Log Output

N/A

Hardware Info

Not relevant