[Impeller] Skip the color blend in drawVertices when using the destination blend mode (#40891)

[Impeller] Skip the color blend in drawVertices when using the destination blend mode

impeller/entity/contents/vertices_contents.cc

diff --git a/impeller/entity/contents/vertices_contents.cc b/impeller/entity/contents/vertices_contents.cc
index e996e09..301a70a 100644
--- a/impeller/entity/contents/vertices_contents.cc
+++ b/impeller/entity/contents/vertices_contents.cc
@@ -68,10 +68,16 @@
 
   auto dst_contents = std::make_shared<VerticesColorContents>(*this);
 
-  auto contents = ColorFilterContents::MakeBlend(
-      blend_mode_, {FilterInput::Make(dst_contents, false),
-                    FilterInput::Make(src_contents, false)});
-  contents->SetAlpha(alpha_);
+  std::shared_ptr<Contents> contents;
+  if (blend_mode_ == BlendMode::kDestination) {
+    contents = dst_contents;
+  } else {
+    auto color_filter_contents = ColorFilterContents::MakeBlend(
+        blend_mode_, {FilterInput::Make(dst_contents, false),
+                      FilterInput::Make(src_contents, false)});
+    color_filter_contents->SetAlpha(alpha_);
+    contents = color_filter_contents;
+  }
 
   return contents->Render(renderer, entity, pass);
 }