Adding blend mode to DrawProperties

cc/trees/layer_tree_host_common.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host_common.h"
 
 #include <algorithm>
 
 #include "base/debug/trace_event.h"
 #include "cc/base/math_util.h"
@@ skipping 1866 matching lines @@
     // The opacity value is moved from the layer to its surface, so that the
     // entire subtree properly inherits opacity.
     render_surface->SetDrawOpacity(accumulated_draw_opacity);
     render_surface->SetDrawOpacityIsAnimating(animating_opacity_to_target);
     animating_opacity_to_target = false;
     layer_draw_properties.opacity = 1.f;
     layer_draw_properties.opacity_is_animating = animating_opacity_to_target;
     layer_draw_properties.screen_space_opacity_is_animating =
         animating_opacity_to_screen;
 
+    // The render surface will be responsible for applying the blend mode.
+    layer_draw_properties.blend_mode = SkXfermode::kSrcOver_Mode;
+
     render_surface->SetTargetSurfaceTransformsAreAnimating(
         animating_transform_to_target);
     render_surface->SetScreenSpaceTransformsAreAnimating(
         animating_transform_to_screen);
     animating_transform_to_target = false;
     layer_draw_properties.target_space_transform_is_animating =
         animating_transform_to_target;
     layer_draw_properties.screen_space_transform_is_animating =
         animating_transform_to_screen;
 
@@ skipping 98 matching lines @@
     DCHECK(layer->parent());
 
     // Note: layer_draw_properties.target_space_transform is computed above,
     // before this if-else statement.
     layer_draw_properties.target_space_transform_is_animating =
         animating_transform_to_target;
     layer_draw_properties.screen_space_transform_is_animating =
         animating_transform_to_screen;
     layer_draw_properties.opacity = accumulated_draw_opacity;
     layer_draw_properties.opacity_is_animating = animating_opacity_to_target;
+    layer_draw_properties.blend_mode = layer->blend_mode();
     layer_draw_properties.screen_space_opacity_is_animating =
         animating_opacity_to_screen;
     data_for_children.parent_matrix = combined_transform;
 
     layer->ClearRenderSurface();
 
     // Layers without render_surfaces directly inherit the ancestor's clip
     // status.
     layer_or_ancestor_clips_descendants = ancestor_clips_subtree;
     if (ancestor_clips_subtree) {
@@ skipping 418 matching lines @@
       inputs->current_render_surface_layer_list_id);
 
   // The dummy layer list should not have been used.
   DCHECK_EQ(0u, dummy_layer_list.size());
   // A root layer render_surface should always exist after
   // CalculateDrawProperties.
   DCHECK(inputs->root_layer->render_surface());
 }
 
 }  // namespace cc