ScrollCaptureConnection: fix npe on close() when active

A reference to the callback was being removed while still
needed. Instead use a local copy for posted callback.

Bug: 12345678
Test: atest ScrollCaptureConnectionTest#testCloseWhileActive
Change-Id: I3a11ac86a8c291972f442ebce962ba8a3a1ddee6

2 files changed, 14 insertions, 1 deletions

diff --git a/core/java/android/view/ScrollCaptureConnection.java b/core/java/android/view/ScrollCaptureConnection.java
index a6d786e1db21..5fcb011c76f1 100644
--- a/core/java/android/view/ScrollCaptureConnection.java
+++ b/core/java/android/view/ScrollCaptureConnection.java
@@ -185,7 +185,8 @@ public class ScrollCaptureConnection extends IScrollCaptureConnection.Stub {
             }
             Log.w(TAG, "close(): capture session still active! Ending now.");
             // -> UiThread
-            mUiThread.execute(() -> mLocal.onScrollCaptureEnd(() -> { /* ignore */ }));
+            final ScrollCaptureCallback callback = mLocal;
+            mUiThread.execute(() -> callback.onScrollCaptureEnd(() -> { /* ignore */ }));
             mActive = false;
         }
         mActive = false;
diff --git a/core/tests/coretests/src/android/view/ScrollCaptureConnectionTest.java b/core/tests/coretests/src/android/view/ScrollCaptureConnectionTest.java
index 22c71b527d48..e7b88c8df393 100644
--- a/core/tests/coretests/src/android/view/ScrollCaptureConnectionTest.java
+++ b/core/tests/coretests/src/android/view/ScrollCaptureConnectionTest.java
@@ -32,6 +32,7 @@ import android.graphics.Point;
 import android.graphics.Rect;
 import android.os.Handler;
 import android.os.ICancellationSignal;
+import android.os.RemoteException;
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
@@ -189,4 +190,15 @@ public class ScrollCaptureConnectionTest {
         verifyNoMoreInteractions(mRemote);
     }
 
+    @Test
+    public void testClose_whileActive() throws RemoteException {
+        mConnection.startCapture(mSurface, mRemote);
+
+        mCallback.completeStartRequest();
+        assertTrue(mConnection.isActive());
+
+        mConnection.close();
+        mCallback.completeEndRequest();
+        assertFalse(mConnection.isActive());
+    }
 }