Track window position with task position.

Windows were previously ordered by TaskStack/ActivityStack order. This
change provides a data structure in DisplayContent that tracks task
movement. Previously Recents and Home activity windows were always
adjacent because they were on the same stack. With this change windows
from other activities can be placed between the two.

Fixes bug 11338594.

Change-Id: Ie34443ff22f330d015141d97db79370c54920d28

1 files changed, 3 insertions, 5 deletions

diff --git a/services/java/com/android/server/wm/WindowManagerService.java b/services/java/com/android/server/wm/WindowManagerService.java
index abc2b2b998e7..4fe204c1d862 100644
--- a/services/java/com/android/server/wm/WindowManagerService.java
+++ b/services/java/com/android/server/wm/WindowManagerService.java
@@ -4733,11 +4733,9 @@ public class WindowManagerService extends IWindowManager.Stub
         return index;
     }
 
-    void moveStackWindowsLocked(TaskStack stack) {
-        DisplayContent displayContent = stack.getDisplayContent();
-
+    void moveStackWindowsLocked(DisplayContent displayContent) {
         // First remove all of the windows from the list.
-        final ArrayList<Task> tasks = stack.getTasks();
+        final ArrayList<Task> tasks = displayContent.getTasks();
         final int numTasks = tasks.size();
         for (int taskNdx = 0; taskNdx < numTasks; ++taskNdx) {
             AppTokenList tokens = tasks.get(taskNdx).mAppTokens;
@@ -4813,7 +4811,7 @@ public class WindowManagerService extends IWindowManager.Stub
                 }
                 final TaskStack stack = task.mStack;
                 stack.moveTaskToBottom(task);
-                moveStackWindowsLocked(stack);
+                moveStackWindowsLocked(stack.getDisplayContent());
             }
         } finally {
             Binder.restoreCallingIdentity(origId);