tree 2b067ca5b48f98ca80f19b6456259277ceb2e9f6
parent cf2ef57519ae1dd0aacb78d69c2fb668c83977cb
author Ashok Mutyala <quic_c_nmutya@quicinc.com> 1628680639 +0000
committer Ashok Mutyala <quic_c_nmutya@quicinc.com> 1628742678 +0000

Avoid the scenario where Contexts list filled with null value in ShowAnrDialogs()

Problem: Framework Reboot i.e., NullPointer Exception in android.ui Thread
E AndroidRuntime: FATAL EXCEPTION IN SYSTEM PROCESS: android.ui
E AndroidRuntime: java.lang.NullPointerException: Attempt to invoke virtual method
'java.lang.Object android.content.Context.getSystemService(java.lang.String)' on a null object reference

E AndroidRuntime: **at android.app.Dialog.<init>(Dialog.java:199)
E AndroidRuntime: **at android.app.AlertDialog.<init>(AlertDialog.java:204)
E AndroidRuntime: **at android.app.AlertDialog.<init>(AlertDialog.java:200)
E AndroidRuntime: **at com.android.server.am.BaseErrorDialog.<init>(BaseErrorDialog.java:39)
E AndroidRuntime: **at com.android.server.am.AppNotRespondingDialog.<init>(AppNotRespondingDialog.java:53)
E AndroidRuntime: **at com.android.server.am.ErrorDialogController.showAnrDialogs(ErrorDialogController.java:183)
E AndroidRuntime: **at com.android.server.am.AppErrors.handleShowAnrUi(AppErrors.java:1077)

Analysis:
As Context Object is passed from showAnrDialogs method and will be retrieved from getDisplayContextWithErrorDialogs
And list of context objects will be filled by querying from RootWindowContainer.getDisplayUiContext and this method is
Annotated with Nullable. So, the possibility could be null value filled in the context object List.

Bug: 196189977
Test: Stability Test

Change-Id: Ib944fc5ffc8bcca999c75f99d462d441e555fcda