meson: Add option flags to control test suites building

Now the `tests` meson option controls weather we should build all the test suites
while `core_tests` controls mutter tests.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/442

meson.build

@@ -246,15 +246,23 @@ if have_introspection
   ]
 endif
 
-have_cogl_tests = get_option('cogl_tests')
-have_clutter_tests = get_option('clutter_tests')
-have_installed_tests = get_option('installed_tests')
-
 have_tests = get_option('tests')
+have_core_tests = false
+have_cogl_tests = false
+have_clutter_tests = false
+have_installed_tests = false
+
 if have_tests
+  have_core_tests = get_option('core_tests')
+  if have_core_tests
     if not have_wayland
       error('Tests require Wayland to be enabled')
     endif
+  endif
+
+  have_cogl_tests = get_option('cogl_tests')
+  have_clutter_tests = get_option('clutter_tests')
+  have_installed_tests = get_option('installed_tests')
 endif
 
 required_functions = [
@@ -405,6 +413,7 @@ output = [
   '    Tests:',
   '',
   '        Enabled.................. ' + have_tests.to_string(),
+  '        Core tests............... ' + have_core_tests.to_string(),
   '        Cogl tests............... ' + have_cogl_tests.to_string(),
   '        Clutter tests............ ' + have_clutter_tests.to_string(),
   '        Installed tests.......... ' + have_installed_tests.to_string(),

meson_options.txt

@@ -111,10 +111,16 @@ option('clutter_tests',
   description: 'Enable clutter tests'
 )
 
+option('core_tests',
+  type: 'boolean',
+  value: true,
+  description: 'Enable mutter core tests'
+)
+
 option('tests',
   type: 'boolean',
   value: true,
-  description: 'Enable mutter tests'
+  description: 'Enable tests globally. Specific test suites can be controlled with core_tests, clutter_tests, and cogl_tests'
 )
 
 option('installed_tests',

src/meson.build

@@ -875,6 +875,6 @@ pkg.generate(libmutter,
 
 subdir('compositor/plugins')
 
-if have_tests 
+if have_core_tests
   subdir('tests')
 endif