Fenix: FNX2-15961 ⁃ [Bug] Fenix crashes when opening tabs tray

[cadeyrn]

Steps to reproduce

1. enable the tabs tray
2. open the tabs tray

Expected behavior

No crash.

Actual behavior

Fenix crashes.

2020-05-06 23:37:06.413 8398-8398/org.mozilla.fenix.debug E/AndroidRuntime: FATAL EXCEPTION: main
    Process: org.mozilla.fenix.debug, PID: 8398
    java.lang.IllegalStateException: Cannot add item decoration during a scroll  or layout
        at androidx.recyclerview.widget.RecyclerView.assertNotInLayoutOrScroll(RecyclerView.java:3053)
        at androidx.recyclerview.widget.RecyclerView$LayoutManager.assertNotInLayoutOrScroll(RecyclerView.java:7898)
        at androidx.recyclerview.widget.LinearLayoutManager.assertNotInLayoutOrScroll(LinearLayoutManager.java:1410)
        at androidx.recyclerview.widget.RecyclerView.addItemDecoration(RecyclerView.java:1569)
        at androidx.recyclerview.widget.RecyclerView.addItemDecoration(RecyclerView.java:1597)
        at org.mozilla.fenix.HomeActivity$onCreateView$adapter$1.invoke(HomeActivity.kt:233)
        at org.mozilla.fenix.HomeActivity$onCreateView$adapter$1.invoke(HomeActivity.kt:93)
        at mozilla.components.browser.tabstray.TabsAdapter.onCreateViewHolder(TabsAdapter.kt:46)
        at mozilla.components.browser.tabstray.TabsAdapter.onCreateViewHolder(TabsAdapter.kt:26)
        at androidx.recyclerview.widget.RecyclerView$Adapter.createViewHolder(RecyclerView.java:7078)
        at androidx.recyclerview.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:6235)
        at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6118)
        at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6114)
        at androidx.recyclerview.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2303)
        at androidx.recyclerview.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1627)
        at androidx.recyclerview.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1587)
        at androidx.recyclerview.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:665)
        at androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:4134)
        at androidx.recyclerview.widget.RecyclerView.onMeasure(RecyclerView.java:3540)
        at android.view.View.measure(View.java:24730)
        at androidx.constraintlayout.widget.ConstraintLayout$Measurer.measure(ConstraintLayout.java:724)
        at androidx.constraintlayout.solver.widgets.analyzer.BasicMeasure.measure(BasicMeasure.java:394)
        at androidx.constraintlayout.solver.widgets.analyzer.BasicMeasure.measureChildren(BasicMeasure.java:105)
        at androidx.constraintlayout.solver.widgets.analyzer.BasicMeasure.solverMeasure(BasicMeasure.java:227)
        at androidx.constraintlayout.solver.widgets.ConstraintWidgetContainer.measure(ConstraintWidgetContainer.java:113)
        at androidx.constraintlayout.widget.ConstraintLayout.resolveSystem(ConstraintLayout.java:1460)
        at androidx.constraintlayout.widget.ConstraintLayout.onMeasure(ConstraintLayout.java:1539)
        at android.view.View.measure(View.java:24730)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6858)
        at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
        at android.view.View.measure(View.java:24730)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6858)
        at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1552)
        at android.widget.LinearLayout.measureVertical(LinearLayout.java:842)
        at android.widget.LinearLayout.onMeasure(LinearLayout.java:721)
        at android.view.View.measure(View.java:24730)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6858)
        at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
        at androidx.appcompat.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:146)
        at android.view.View.measure(View.java:24730)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6858)
        at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1552)
        at android.widget.LinearLayout.measureVertical(LinearLayout.java:842)
        at android.widget.LinearLayout.onMeasure(LinearLayout.java:721)
        at android.view.View.measure(View.java:24730)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6858)
2020-05-06 23:37:06.414 8398-8398/org.mozilla.fenix.debug E/AndroidRuntime:     at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
        at android.view.View.measure(View.java:24730)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6858)
        at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1552)
        at android.widget.LinearLayout.measureVertical(LinearLayout.java:842)
        at android.widget.LinearLayout.onMeasure(LinearLayout.java:721)
        at android.view.View.measure(View.java:24730)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6858)
        at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
        at com.android.internal.policy.DecorView.onMeasure(DecorView.java:749)
        at android.view.View.measure(View.java:24730)
        at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:3264)
        at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:2047)
        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2342)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1935)
        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:8023)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:1163)
        at android.view.Choreographer.doCallbacks(Choreographer.java:986)
        at android.view.Choreographer.doFrame(Choreographer.java:902)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:1148)
        at android.os.Handler.handleCallback(Handler.java:883)
        at android.os.Handler.dispatchMessage(Handler.java:100)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7695)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)

It's a regression from #10325. /cc @darkwing

Device information

• Android device: OnePlus 7T Pro McLaren Edition / Oxygen OS 10.0.8 (Android 10)
• Fenix version: master branch revision 8b27a486355e45219c5f9e5d58b7c5274c193be3

[mcarare]

I can confirm the crash and the regression origin. Thanks @cadeyrn!

[pocmo]

CC @darkwing, @boek

@Mugurell and I decided to not backout the patch since it only affects users that have explicitly enabled the new tabs tray in the hidden settings screen.

[andreicristianpetcu]

It's fixed for me

[cadeyrn]

I can confirm that Fenix no longer crashes. Since it affects a hidden feature I'll just close the issue. I don't think additional QA verification is needed. If you disagree please reopen. :)