ozone: Add overlay candidate implementation that queries support via IPC

ui/ozone/common/gpu/ozone_gpu_message_params.cc

 // Copyright 2014 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.
 
 #include "ui/ozone/common/gpu/ozone_gpu_message_params.h"
 
+#include "ui/gfx/geometry/rect_conversions.h"
+#include "ui/gfx/ipc/gfx_param_traits.h"
+
 namespace ui {
 
 DisplayMode_Params::DisplayMode_Params()
     : size(), is_interlaced(false), refresh_rate(0.0f) {}
 
 DisplayMode_Params::~DisplayMode_Params() {}
 
 DisplaySnapshot_Params::DisplaySnapshot_Params()
     : display_id(0),
       origin(),
       physical_size(),
       type(ui::DISPLAY_CONNECTION_TYPE_NONE),
       is_aspect_preserving_scaling(false),
       has_overscan(false),
       display_name(),
       modes(),
       has_current_mode(false),
       current_mode(),
       has_native_mode(false),
       native_mode(),
       product_id(0) {
 }
 
 DisplaySnapshot_Params::~DisplaySnapshot_Params() {}
 
+OverlayCheck_Params::OverlayCheck_Params()
+    : transform(gfx::OVERLAY_TRANSFORM_INVALID),
+      format(SurfaceFactoryOzone::UNKNOWN),
+      plane_z_order(0) {
+}
+
+OverlayCheck_Params::OverlayCheck_Params(
+    const OverlayCandidatesOzone::OverlaySurfaceCandidate& candidate)
+    : buffer_size(candidate.buffer_size),
+      transform(candidate.transform),
+      format(candidate.format),
+      display_rect(gfx::ToNearestRect(candidate.display_rect)),

[spang, 2015/06/01 18:54:20]

why is it a RectF in OverlayCandidatesOzone and a Rect in OverlayCheck_Params?

[achaulk, 2015/06/01 20:43:08]

We convert to ints internally, this is post-conversion

+      plane_z_order(candidate.plane_z_order) {
+}
+
+OverlayCheck_Params::~OverlayCheck_Params() {
+}
+
 }  // namespace ui