[Impeller] remove absorb opacity limit. (#52160)

Both contents correctly check for absorb opacity so I think this is pointless.

Author: Jonah Williams

impeller/entity/contents/filters/blend_filter_contents.cc

@@ -728,8 +728,7 @@ std::optional<Entity> BlendFilterContents::RenderFilter(
   }
 
   if (blend_mode_ <= Entity::kLastPipelineBlendMode) {
-    if (inputs.size() == 1 && foreground_color_.has_value() &&
-        GetAbsorbOpacity() == ColorFilterContents::AbsorbOpacity::kYes) {
+    if (inputs.size() == 1 && foreground_color_.has_value()) {
       return CreateForegroundPorterDuffBlend(
           inputs[0], renderer, entity, coverage, foreground_color_.value(),
           blend_mode_, GetAlpha(), GetAbsorbOpacity());
@@ -739,8 +738,7 @@ std::optional<Entity> BlendFilterContents::RenderFilter(
   }
 
   if (blend_mode_ <= Entity::kLastAdvancedBlendMode) {
-    if (inputs.size() == 1 && foreground_color_.has_value() &&
-        GetAbsorbOpacity() == ColorFilterContents::AbsorbOpacity::kYes) {
+    if (inputs.size() == 1 && foreground_color_.has_value()) {
       return CreateForegroundAdvancedBlend(
           inputs[0], renderer, entity, coverage, foreground_color_.value(),
           blend_mode_, GetAlpha(), GetAbsorbOpacity());