FUCHSIA: meson: add platforms 'none'

This is used when building for Fuchsia, which doesn't offer SDK
support for Vulkan WSI.

Change-Id: Id3ccbbfdfb8b5c0c14fca8dec52d1f5a6e1f5ac0

meson.build

@@ -384,6 +384,10 @@ with_platform_x11 = _platforms.contains('x11')
 with_platform_wayland = _platforms.contains('wayland')
 with_platform_haiku = _platforms.contains('haiku')
 with_platform_windows = _platforms.contains('windows')
+with_platform_none = _platforms.contains('none')
+if with_platform_none and _platforms.length() > 1
+  error('Platforms cannot be combined with \'none\'')
+endif
 
 with_glx = get_option('glx')
 if with_glx == 'auto'

meson_options.txt

@@ -12,7 +12,7 @@ option(
   type : 'array',
   value : ['auto'],
   choices : [
-    'auto', 'x11', 'wayland', 'haiku', 'android', 'windows',
+    'auto', 'x11', 'wayland', 'haiku', 'android', 'windows', 'none',
   ],
   description : 'window systems to support. If this is set to `auto`, all ' +
                 'platforms applicable will be enabled.'

src/vulkan/wsi/meson.build

@@ -1,10 +1,14 @@
 # Copyright © 2017 Intel Corporation
 # SPDX-License-Identifier: MIT
 
-files_vulkan_wsi = files('wsi_common.c')
+files_vulkan_wsi = []
 links_vulkan_wsi = []
 platform_deps = []
 
+if not with_platform_none
+  files_vulkan_wsi += files('wsi_common.c')
+endif
+
 if dep_libdrm.found()
   files_vulkan_wsi += files('wsi_common_drm.c')
 endif
@@ -25,7 +29,7 @@ endif
 if with_platform_windows
   files_vulkan_wsi += files('wsi_common_win32.cpp')
   platform_deps += dep_dxheaders
-else
+elif not with_platform_none
   files_vulkan_wsi += files('wsi_common_headless.c')
 endif