exo: Add support for importing YVU_420 buffers.

components/exo/wayland/server.cc

Index: components/exo/wayland/server.cc
diff --git a/components/exo/wayland/server.cc b/components/exo/wayland/server.cc
index 61c0c6baa3b3e71871f28b4228b67140a1ba345b..a4486041c0e74f5cbf9c3f70d443dc515eec9e0f 100644
--- a/components/exo/wayland/server.cc
+++ b/components/exo/wayland/server.cc
@@ -55,6 +55,8 @@
 #include "ui/display/display_observer.h"
 #include "ui/display/screen.h"
 #include "ui/events/keycodes/dom/keycode_converter.h"
+#include "ui/gfx/buffer_format_util.h"
+#include "ui/gfx/buffer_types.h"
 #include "ui/views/widget/widget.h"
 #include "ui/views/widget/widget_observer.h"
 #include "ui/wm/public/activation_change_observer.h"
@@ -435,6 +437,7 @@ const struct drm_supported_format {
   uint32_t drm_format;
   gfx::BufferFormat buffer_format;
 } drm_supported_formats[] = {
+    {WL_DRM_FORMAT_YUV420, gfx::BufferFormat::YUV_420},
     {WL_DRM_FORMAT_RGB565, gfx::BufferFormat::BGR_565},
     {WL_DRM_FORMAT_XBGR8888, gfx::BufferFormat::RGBX_8888},
     {WL_DRM_FORMAT_ABGR8888, gfx::BufferFormat::RGBA_8888},
@@ -500,10 +503,17 @@ void drm_create_prime_buffer(wl_client* client,
     return;
   }
 
+  std::vector<int> strides{stride0, stride1, stride2};
+  std::vector<int> offsets{offset0, offset1, offset2};
+
+  int planes =
+      gfx::NumberOfPlanesForBufferFormat(supported_format->buffer_format);
+  strides.resize(planes);
+  offsets.resize(planes);
   std::unique_ptr<Buffer> buffer =
       GetUserDataAs<Display>(resource)->CreateLinuxDMABufBuffer(
           base::ScopedFD(name), gfx::Size(width, height),
-          supported_format->buffer_format, stride0);
+          supported_format->buffer_format, strides, offsets);
   if (!buffer) {
     wl_resource_post_no_memory(resource);
     return;
@@ -544,6 +554,7 @@ const struct dmabuf_supported_format {
   uint32_t dmabuf_format;
   gfx::BufferFormat buffer_format;
 } dmabuf_supported_formats[] = {
+    // TODO(dcastagna): Add support for YUV_420.

[reveman, 2016/06/06 21:24:08]

Please add this format here as well. The interface above is the deprecated
version that we'll remove in the near future.

[Daniele Castagna, 2016/06/09 21:09:17]

Done. Added also the support for multiple planes in LinuxBufferParams.

     {DRM_FORMAT_RGB565, gfx::BufferFormat::BGR_565},
     {DRM_FORMAT_XBGR8888, gfx::BufferFormat::RGBX_8888},
     {DRM_FORMAT_ABGR8888, gfx::BufferFormat::RGBA_8888},
@@ -636,7 +647,7 @@ void linux_buffer_params_create(wl_client* client,
   std::unique_ptr<Buffer> buffer =
       linux_buffer_params->display->CreateLinuxDMABufBuffer(
           std::move(linux_buffer_params->fd), gfx::Size(width, height),
-          supported_format->buffer_format, linux_buffer_params->stride);
+          supported_format->buffer_format, {linux_buffer_params->stride}, {0});
   if (!buffer) {
     zwp_linux_buffer_params_v1_send_failed(resource);
     return;