From 01481c8d5821a8dd5850e9f46389b3d84a97f1a4 Mon Sep 17 00:00:00 2001
From: Nicolas Silva <nsilva@mozilla.com>
Date: Fri, 9 Aug 2019 03:50:47 +0000
Subject: [PATCH] Bug 1570543 - Fix incorrect batch index after merging
 batches. r=gw

Differential Revision: https://phabricator.services.mozilla.com/D41166

--HG--
extra : moz-landing-system : lando
---
 gfx/wr/webrender/src/batch.rs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/gfx/wr/webrender/src/batch.rs b/gfx/wr/webrender/src/batch.rs
index 50df897adcee..a49387dc3138 100644
--- a/gfx/wr/webrender/src/batch.rs
+++ b/gfx/wr/webrender/src/batch.rs
@@ -429,8 +429,9 @@ impl AlphaBatchContainer {
 
             match batch_index {
                 Some(batch_index) => {
-                    self.alpha_batches[batch_index + min_batch_index].merge(other_batch);
-                    min_batch_index = batch_index;
+                    let index = batch_index + min_batch_index;
+                    self.alpha_batches[index].merge(other_batch);
+                    min_batch_index = index;
                 }
                 None => {
                     self.alpha_batches.push(other_batch);