object: Use g_object_new_with_properties()

g_object_newv() is deprecated, and we had deprecation guards around it in
order to silence the deprecation warning. Since we're going to refactor
this code, it's probably time to fix this.

We get rid of the awkward clear() function by moving it into the
destructor of an AutoGValueVector class.

GLib dependency is now 2.54.

Closes: #104
17 jobs for 104-g-object-new-with-properties in 27 minutes and 49 seconds (queued for 9 seconds)
Status Job ID Name Coverage
  Source Check
passed #45017
cppcheck

00:02:31

passed #45018
cpplint

00:04:31

passed #45019
eslint

00:03:59

passed #45016
fedora

00:02:19

 
  Test
passed #45020
fedora_clang

00:04:39

 
  Thorough Tests
passed #45023
coverage

00:18:34

passed #45022
installed_tests

00:04:55

manual #45028
allowed to fail manual
lts
manual #45027
allowed to fail manual
no_graphics
passed #45021
no_profiler

00:02:07

passed #45024
sanitizer_gcc

00:10:56

manual #45026
allowed to fail manual
valgrind
passed #45025
with_logging

00:05:12

manual #45031
allowed to fail manual
zeal_11
manual #45029
allowed to fail manual
zeal_2
manual #45030
allowed to fail manual
zeal_4
 
  Delivery
manual #45032
allowed to fail manual
packaging