From 411db2d587b4b3d888d7d3ba6ab622560960cb78 Mon Sep 17 00:00:00 2001
From: Ian Hickson <ian@hixie.ch>
Date: Fri, 9 Sep 2016 14:25:34 -0700
Subject: [PATCH] Tabs occasionally tried to setState after dispose (#5784)

Fixes https://github.com/flutter/flutter/issues/5776
---
 dev/benchmarks/microbenchmarks/README.md               |  8 ++++----
 .../microbenchmarks/lib/stocks/layout_bench.dart       |  1 -
 packages/flutter/lib/src/material/tabs.dart            | 10 ++++++----
 3 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/dev/benchmarks/microbenchmarks/README.md b/dev/benchmarks/microbenchmarks/README.md
index 6f6e31758be..1c7d38319f5 100644
--- a/dev/benchmarks/microbenchmarks/README.md
+++ b/dev/benchmarks/microbenchmarks/README.md
@@ -3,10 +3,10 @@
 To run these benchmarks on a device:
 
 ```
-flutter run --release -t lib/gestures/velocity_tracker_data.dart
-flutter run --release -t lib/stocks/animation_bench.dart
-flutter run --release -t lib/stocks/build_bench.dart
-flutter run --release -t lib/stocks/layout_bench.dart
+flutter run --release lib/gestures/velocity_tracker_data.dart
+flutter run --release lib/stocks/animation_bench.dart
+flutter run --release lib/stocks/build_bench.dart
+flutter run --release lib/stocks/layout_bench.dart
 ```
 
 The results should be in the device logs.
diff --git a/dev/benchmarks/microbenchmarks/lib/stocks/layout_bench.dart b/dev/benchmarks/microbenchmarks/lib/stocks/layout_bench.dart
index 0a1d1999012..20902fe567c 100644
--- a/dev/benchmarks/microbenchmarks/lib/stocks/layout_bench.dart
+++ b/dev/benchmarks/microbenchmarks/lib/stocks/layout_bench.dart
@@ -11,7 +11,6 @@ const Duration kBenchmarkTime = const Duration(seconds: 15);
 
 
 Future<Null> main() async {
-  assert(false); // don't run this in checked mode! Use --release.
   stock_data.StockDataFetcher.actuallyFetchData = false;
 
   final Stopwatch watch = new Stopwatch();
diff --git a/packages/flutter/lib/src/material/tabs.dart b/packages/flutter/lib/src/material/tabs.dart
index 227dd635c24..3f5d566dcd7 100644
--- a/packages/flutter/lib/src/material/tabs.dart
+++ b/packages/flutter/lib/src/material/tabs.dart
@@ -977,10 +977,12 @@ class _TabBarState<T> extends ScrollableState<TabBar<T>> implements TabBarSelect
     _indicatorRect = _selection != null ? _tabIndicatorRect(_selection.index) : Rect.zero;
     _updateScrollBehavior();
     SchedulerBinding.instance.addPostFrameCallback((Duration timeStamp) {
-      setState(() {
-        // the changes were made at layout time
-        // TODO(ianh): remove this setState: https://github.com/flutter/flutter/issues/5749
-      });
+      if (mounted) {
+        setState(() {
+          // the changes were made at layout time
+          // TODO(ianh): remove this setState: https://github.com/flutter/flutter/issues/5749
+        });
+      }
     });
   }