Make spinner spin by default in "Loading app details..." page
This fixes the issue where the GtkSpinner
is not displayed until the
details page switches to a non-default state (state != GS_DETAILS_PAGE_STATE_LOADING)
.
This is due to the state == gs_details_page_get_state (self)
check
in gs_details_page_set_state ()
, which will be true for the first
few runs. Rather than handling this in code, we fix it in UI file.