ozone: Add ability to set clinet capabilities which we will need for atomic

ui/ozone/platform/drm/drm.gypi

Index: ui/ozone/platform/drm/drm.gypi
diff --git a/ui/ozone/platform/drm/drm.gypi b/ui/ozone/platform/drm/drm.gypi
index 532f62ea2d0656b60d3a4a4b4f0523f8e8b79041..4947784503befe3aceddb2d7069453c83a42b42f 100644
--- a/ui/ozone/platform/drm/drm.gypi
+++ b/ui/ozone/platform/drm/drm.gypi
@@ -104,6 +104,15 @@
         'ozone_platform_drm.h',
         'scanout_buffer.h',
       ],
+      'conditions': [
+        # This is only present in actual device builds so we use it as a flag
+        # here to filter out code that can't run on the bots.
+        ['use_evdev_gestures==1', {

[dnicoara, 2015/05/14 17:43:18]

Lets not re-use event related defines for this kind of behavior. Add a DRM
specific flag.

+          'defines': [
+            'IS_DEVICE_BUILD',

[dnicoara, 2015/05/14 17:43:18]

You should also name this appropriately.

[achaulk, 2015/05/14 18:26:24]

To what? OS_IS_REALLY_CHROMEOS?

[dnicoara, 2015/05/14 18:31:37]

To SUPPORTS_SET_CLIENT_CAP or something similar. If you want, you can even use
'pkg-config --version libdrm' to figure out if the supplied version supports
said feature.

[achaulk, 2015/05/14 18:33:13]

We're also going to need to condition the atomic apis on this flag too, maybe
HAS_CHROMEOS_DRM?

[dnicoara, 2015/05/14 18:38:15]

How about HAS_ATOMIC_DRM_API? Just because chromeos has it doesn't mean that you
can't build outside the CrOS chroot.

+          ],
+        }]
+      ],
     },
     {
       'target_name': 'ozone_platform_drm_unittests',