From be73e88f17ed3db63c53c72c320bcec0949eed9b Mon Sep 17 00:00:00 2001
From: Brandon DeRosier <bdero@google.com>
Date: Thu, 25 May 2023 09:32:23 -0700
Subject: [PATCH] [Impeller] Safely access snapshot in the pipeline blend
 filter (flutter/engine#42314)

Spotted by @zanderso.
---
 .../impeller/entity/contents/filters/blend_filter_contents.cc  | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/engine/src/flutter/impeller/entity/contents/filters/blend_filter_contents.cc b/engine/src/flutter/impeller/entity/contents/filters/blend_filter_contents.cc
index 1c320657e8..287ec60ee3 100644
--- a/engine/src/flutter/impeller/entity/contents/filters/blend_filter_contents.cc
+++ b/engine/src/flutter/impeller/entity/contents/filters/blend_filter_contents.cc
@@ -484,6 +484,9 @@ static std::optional<Entity> PipelineBlend(
 
   auto dst_snapshot =
       inputs[0]->GetSnapshot("PipelineBlend(Dst)", renderer, entity);
+  if (!dst_snapshot.has_value()) {
+    return std::nullopt;
+  }
 
   ContentContext::SubpassCallback callback = [&](const ContentContext& renderer,
                                                  RenderPass& pass) {