Fix screenshotting with includeDecor=true in multi-window

The old code wasn't really tested and stackBounds variable was
null in any case.

Test: Go to multi-window, go to recents, make sure screenshot is
correct.
Bug: 31339431

Change-Id: I721397800ba7519dba7f569461c5f339eba0591b

1 files changed, 5 insertions, 4 deletions

diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index 592eaec7f31d..3e703b2fb3b0 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -2252,10 +2252,11 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
                 }
 
                 // Don't include wallpaper in bounds calculation
-                if (includeDecor && !stackBounds.isEmpty()) {
-                    frame.set(stackBounds);
-                } else if (includeDecor) {
-                    mutableIncludeFullDisplay.value = true;
+                if (!mutableIncludeFullDisplay.value && includeDecor) {
+                    final TaskStack stack = w.getStack();
+                    if (stack != null) {
+                        stack.getBounds(frame);
+                    }
                 } else if (!mutableIncludeFullDisplay.value && !w.mIsWallpaper) {
                     final Rect wf = w.mFrame;
                     final Rect cr = w.mContentInsets;