ozone: Allocate scanout buffer according to KMS modifiers

ui/ozone/platform/drm/gpu/gbm_buffer.h

Index: ui/ozone/platform/drm/gpu/gbm_buffer.h
diff --git a/ui/ozone/platform/drm/gpu/gbm_buffer.h b/ui/ozone/platform/drm/gpu/gbm_buffer.h
index e38a50f75734788539dfb9eff1d5ed197c57ba28..74a2f0c0a7df624bd79fdf03d5810ae4ac21d519 100644
--- a/ui/ozone/platform/drm/gpu/gbm_buffer.h
+++ b/ui/ozone/platform/drm/gpu/gbm_buffer.h
@@ -28,6 +28,12 @@ class GbmBuffer : public GbmBufferBase {
       uint32_t format,
       const gfx::Size& size,
       uint32_t usage);
+  static scoped_refptr<GbmBuffer> CreateBufferWithModifiers(

[Daniele Castagna, 2016/12/16 00:27:41]

Why do we need CreateBufferWithModifiers? Can't we just add modifiers to
CreateBuffer?

[hoegsberg1, 2016/12/17 01:10:49]

Hm, I suppose we could just do that. It's a little subtle though that in case it
receive a modifier list it completely ignores the flags. So you get different
semantics whether or not you pass in a modifier vector.

[dnicoara, 2016/12/19 19:44:46]

Should |flags| be removed from the definition then?

+      const scoped_refptr<GbmDevice>& gbm,
+      uint32_t format,
+      const gfx::Size& size,
+      uint32_t flags,
+      const uint64_t *modifiers, uint32_t nmodifiers);
   static scoped_refptr<GbmBuffer> CreateBufferFromFds(
       const scoped_refptr<GbmDevice>& gbm,
       uint32_t format,
@@ -50,6 +56,7 @@ class GbmBuffer : public GbmBufferBase {
             gbm_bo* bo,
             uint32_t format,
             uint32_t flags,
+            uint64_t modifier,
             std::vector<base::ScopedFD>&& fds,
             const gfx::Size& size,
             const std::vector<gfx::NativePixmapPlane>&& planes);
@@ -57,6 +64,7 @@ class GbmBuffer : public GbmBufferBase {
 
   uint32_t format_;
   uint32_t flags_;
+  uint64_t modifier_;
   std::vector<base::ScopedFD> fds_;
   gfx::Size size_;