From 16b6b5109a1b1023d859bf9a46040387f24f3c20 Mon Sep 17 00:00:00 2001
From: Taran Singh <tarandeep@google.com>
Date: Mon, 7 Aug 2023 20:48:48 +0000
Subject: [PATCH] Invalidate stylus handwriting availability cache

In [1] we introduced caching of attributes that determines if stylus
handwriting is available. The strategy used to invalidate cache on IME unbind.
However, a stale value of
InputMethodInfo#supportsStylusHandwriting can be cached if IMM#isStylusHandwritingAvailable() previous IME unbinds and the next one isn't yet connected.
A better approach would be to cache the value on the new IME service connection.

[1]: I6d89d82589e4946e07bfbc4b97811fe4537b1a9b

Bug: 288618291
Bug: 294162601

Test: atest InputMethodServiceLifecycleTest

Change-Id: I35013b6194a67656aefca004e69cfc64f12c1e88
Merged-In: I35013b6194a67656aefca004e69cfc64f12c1e88
---
 .../server/inputmethod/InputMethodBindingController.java    | 6 ++++++
 .../server/inputmethod/InputMethodManagerService.java       | 1 -
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/services/core/java/com/android/server/inputmethod/InputMethodBindingController.java b/services/core/java/com/android/server/inputmethod/InputMethodBindingController.java
index ba9e280be49d0..53083366b0417 100644
--- a/services/core/java/com/android/server/inputmethod/InputMethodBindingController.java
+++ b/services/core/java/com/android/server/inputmethod/InputMethodBindingController.java
@@ -40,6 +40,7 @@ import android.util.Slog;
 import android.view.WindowManager;
 import android.view.inputmethod.InputMethod;
 import android.view.inputmethod.InputMethodInfo;
+import android.view.inputmethod.InputMethodManager;
 
 import com.android.internal.annotations.GuardedBy;
 import com.android.internal.annotations.VisibleForTesting;
@@ -295,7 +296,12 @@ final class InputMethodBindingController {
                     }
                     if (DEBUG) Slog.v(TAG, "Initiating attach with token: " + mCurToken);
                     final InputMethodInfo info = mMethodMap.get(mSelectedMethodId);
+                    boolean supportsStylusHwChanged =
+                            mSupportsStylusHw != info.supportsStylusHandwriting();
                     mSupportsStylusHw = info.supportsStylusHandwriting();
+                    if (supportsStylusHwChanged) {
+                        InputMethodManager.invalidateLocalStylusHandwritingAvailabilityCaches();
+                    }
                     mService.initializeImeLocked(mCurMethod, mCurToken);
                     mService.scheduleNotifyImeUidToAudioService(mCurMethodUid);
                     mService.reRequestCurrentClientSessionLocked();
diff --git a/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java b/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java
index cfcb4620bf25e..771ac9481a758 100644
--- a/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java
+++ b/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java
@@ -2369,7 +2369,6 @@ public final class InputMethodManagerService extends IInputMethodManager.Stub
             mCurVirtualDisplayToScreenMatrix = null;
             ImeTracker.forLogging().onFailed(mCurStatsToken, ImeTracker.PHASE_SERVER_WAIT_IME);
             mCurStatsToken = null;
-            InputMethodManager.invalidateLocalStylusHandwritingAvailabilityCaches();
             mMenuController.hideInputMethodMenuLocked();
         }
     }