From 4d7369adb3cf0e713d25abaefa74d6627ecb086e Mon Sep 17 00:00:00 2001
From: Chong Zhang <chz@google.com>
Date: Mon, 25 Apr 2016 16:09:14 -0700
Subject: [PATCH] Request a wallpaper update pass when wallpaper target is set
 to visible

Usually wallpaper target gets updated when some wallpaper target window
finishes drawing. However in some cases, Recents app could be set to
visible again before its stopped. (Which could happen when we started
opening transition into some app with a saved surface, but the app draws
so slow so that when user pressed Recents button again, the app still
hasn't delivered first frame.) In this case, the surface is already
drawn and we won't get a finish drawing again. We need to make sure the
wallpaper target is updated.

bug: 27742244
Change-Id: I8ff53f15f95bae8a99a5a0fd11e24e0186dc3345
---
 .../java/com/android/server/wm/AppWindowToken.java     |  7 +++++++
 .../com/android/server/wm/WindowManagerService.java    |  2 ++
 .../core/java/com/android/server/wm/WindowState.java   | 10 ++++++++++
 3 files changed, 19 insertions(+)

diff --git a/services/core/java/com/android/server/wm/AppWindowToken.java b/services/core/java/com/android/server/wm/AppWindowToken.java
index 9f54b53739537..3b1f34a30529e 100644
--- a/services/core/java/com/android/server/wm/AppWindowToken.java
+++ b/services/core/java/com/android/server/wm/AppWindowToken.java
@@ -515,6 +515,13 @@ class AppWindowToken extends WindowToken {
         }
     }
 
+    void requestUpdateWallpaperIfNeeded() {
+        for (int i = allAppWindows.size() - 1; i >= 0; i--) {
+            final WindowState w = allAppWindows.get(i);
+            w.requestUpdateWallpaperIfNeeded();
+        }
+    }
+
     boolean isRelaunching() {
         return mPendingRelaunchCount > 0;
     }
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java
index 0b66959ec4bc8..1b9a46a411ef5 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -4422,6 +4422,8 @@ public class WindowManagerService extends IWindowManager.Stub
                         wtoken.sendAppVisibilityToClients();
                     }
                 }
+                wtoken.requestUpdateWallpaperIfNeeded();
+
                 if (DEBUG_ADD_REMOVE) Slog.v(
                         TAG_WM, "No longer Stopped: " + wtoken);
                 wtoken.mAppStopped = false;
diff --git a/services/core/java/com/android/server/wm/WindowState.java b/services/core/java/com/android/server/wm/WindowState.java
index 2c5b035741569..f4e6321172a75 100644
--- a/services/core/java/com/android/server/wm/WindowState.java
+++ b/services/core/java/com/android/server/wm/WindowState.java
@@ -72,6 +72,7 @@ import static android.view.WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
 import static android.view.WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL;
 import static android.view.WindowManager.LayoutParams.FLAG_SCALED;
 import static android.view.WindowManager.LayoutParams.FLAG_SECURE;
+import static android.view.WindowManager.LayoutParams.FLAG_SHOW_WALLPAPER;
 import static android.view.WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED;
 import static android.view.WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON;
 import static android.view.WindowManager.LayoutParams.LAST_SUB_WINDOW;
@@ -89,6 +90,7 @@ import static android.view.WindowManager.LayoutParams.TYPE_DOCK_DIVIDER;
 import static android.view.WindowManager.LayoutParams.TYPE_INPUT_METHOD;
 import static android.view.WindowManager.LayoutParams.TYPE_INPUT_METHOD_DIALOG;
 import static android.view.WindowManager.LayoutParams.TYPE_WALLPAPER;
+import static android.view.WindowManagerPolicy.FINISH_LAYOUT_REDO_WALLPAPER;
 import static com.android.server.wm.DragResizeMode.DRAG_RESIZE_MODE_DOCKED_DIVIDER;
 import static com.android.server.wm.DragResizeMode.DRAG_RESIZE_MODE_FREEFORM;
 import static com.android.server.wm.WindowManagerDebugConfig.DEBUG_ADD_REMOVE;
@@ -2710,6 +2712,14 @@ final class WindowState implements WindowManagerPolicy.WindowState {
         mAnimateReplacingWindow = false;
     }
 
+    void requestUpdateWallpaperIfNeeded() {
+        if (mDisplayContent != null && (mAttrs.flags & FLAG_SHOW_WALLPAPER) != 0) {
+            mDisplayContent.pendingLayoutChanges |= FINISH_LAYOUT_REDO_WALLPAPER;
+            mDisplayContent.layoutNeeded = true;
+            mService.mWindowPlacerLocked.requestTraversal();
+        }
+    }
+
     float translateToWindowX(float x) {
         float winX = x - mFrame.left;
         if (mEnforceSizeCompat) {