ozone: Add an opaque fb to ScanoutBuffer for primary planes.

ui/ozone/platform/drm/gpu/mock_scanout_buffer.cc

Index: ui/ozone/platform/drm/gpu/mock_scanout_buffer.cc
diff --git a/ui/ozone/platform/drm/gpu/mock_scanout_buffer.cc b/ui/ozone/platform/drm/gpu/mock_scanout_buffer.cc
index d372f8e9654eb2fa339168e0c34967c35813a97d..91c0082d97914e23404df76981dca81166dee434 100644
--- a/ui/ozone/platform/drm/gpu/mock_scanout_buffer.cc
+++ b/ui/ozone/platform/drm/gpu/mock_scanout_buffer.cc
@@ -15,6 +15,10 @@ uint32_t MockScanoutBuffer::GetFramebufferId() const {
   return 1;
 }
 
+uint32_t MockScanoutBuffer::GetOpaqueFramebufferId() const {
+  return 2;
+}
+
 uint32_t MockScanoutBuffer::GetHandle() const {
   return 0;
 }
@@ -27,6 +31,10 @@ uint32_t MockScanoutBuffer::GetFramebufferPixelFormat() const {
   return format_;
 }
 
+uint32_t MockScanoutBuffer::GetOpaqueFramebufferPixelFormat() const {
+  return format_;
+}
+
 const DrmDevice* MockScanoutBuffer::GetDrmDevice() const {
   return nullptr;
 }