Add initial unit tests for Provider

Largely cribbed from libhandy, thanks due to Guido.

tests/meson.build

@@ -0,0 +1,46 @@
+if get_option('tests')
+
+test_env = [
+  'G_TEST_SRCDIR=@0@'.format(meson.current_source_dir()),
+  'G_TEST_BUILDDIR=@0@'.format(meson.current_build_dir()),
+  'G_DEBUG=gc-friendly,fatal-warnings',
+  'GSETTINGS_BACKEND=memory',
+  'PYTHONDONTWRITEBYTECODE=yes',
+  'MALLOC_CHECK_=2',
+]
+
+test_cflags = [
+  '-fPIE',
+]
+
+test_link_args = [
+  '-fPIC',
+]
+
+test_names = [
+  'test-provider',
+]
+
+test_calls_source_arrays = [ calls_sources, calls_dummy_sources ]
+
+test_calls_sources = []
+foreach source_array : test_calls_source_arrays
+  foreach source : source_array
+    test_calls_sources += join_paths('..', 'src', source)
+  endforeach
+endforeach
+
+foreach test_name : test_names
+  t = executable(test_name, test_name + '.c',
+                 test_calls_sources, calls_enum_sources, calls_resources,
+		 c_args : test_cflags,
+		 link_args: test_link_args,
+                 link_with : gdbofono_lib,
+	         dependencies: calls_deps,
+                 include_directories : include_directories('..',
+                                                           join_paths('..', 'src')),
+		)
+  test(test_name, t, env: test_env)
+endforeach
+
+endif