Add format modifier IDs for EGL_EXT_image_dma_buf_import extension

ui/gfx/native_pixmap_handle_ozone.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_GFX_NATIVE_PIXMAP_HANDLE_OZONE_H_
 #define UI_GFX_NATIVE_PIXMAP_HANDLE_OZONE_H_
 
 #include <stdint.h>
 #include <vector>
 
 #include "base/file_descriptor_posix.h"
 #include "ui/gfx/gfx_export.h"
 
 namespace gfx {
 
+// GbmBufferPlane is used to carry the plane related information for GBM
+// buffer. More fields can be added if they are plane specific.
+struct GFX_EXPORT GbmBufferPlane {
+  GbmBufferPlane();
+  GbmBufferPlane(int stride, int offset, uint64_t modifier);
+  GbmBufferPlane(const GbmBufferPlane& other);
+  ~GbmBufferPlane();
+
+  // The strides and offsets in bytes to be used when accessing the buffers via
+  // a memory mapping. One per plane per entry.
+  int stride;
+  int offset;
+  // The modifiers is retrieved from GBM library and passed to EGL driver.

[Daniele Castagna, 2016/06/15 17:30:09]

nit: s/modifiers/modifier or make the verb plural.

[vinceh, 2016/06/16 02:08:44]

Oops. Will fix.

+  // Generally it's platform specific, and we don't need to modify it in
+  // browser code. Also one per plane per entry.

[Daniele Castagna, 2016/06/15 17:30:09]

nit: if you use the term browser in chromium, we probably think about the
browser process and not about the whole thing. Maybe you can refer to it as
Chromium code instead?

[vinceh, 2016/06/16 02:08:44]

Yes, will fix.

+  uint64_t modifier;
+};
+
 struct GFX_EXPORT NativePixmapHandle {
   NativePixmapHandle();
   NativePixmapHandle(const NativePixmapHandle& other);
 
   ~NativePixmapHandle();
   // File descriptors for the underlying memory objects (usually dmabufs).
   std::vector<base::FileDescriptor> fds;
 
-  // The strides and offsets in bytes to be used when accessing the buffers via
-  // a memory mapping. One per plane per entry.
-  std::vector<std::pair<int, int>> strides_and_offsets;
+  std::vector<GbmBufferPlane> planes;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_NATIVE_PIXMAP_HANDLE_OZONE_H_