4 files changed, 16 insertions, 14 deletions

diff --git a/core/java/android/service/wallpaper/WallpaperService.java b/core/java/android/service/wallpaper/WallpaperService.java
index dd78c78654c3..e9285cc7931d 100644
--- a/core/java/android/service/wallpaper/WallpaperService.java
+++ b/core/java/android/service/wallpaper/WallpaperService.java
@@ -223,6 +223,9 @@ public abstract class WallpaperService extends Service {
 
         SurfaceControl mSurfaceControl = new SurfaceControl();
 
+        // Unused relayout out-param
+        SurfaceControl mTmpSurfaceControl = new SurfaceControl();
+
         final BaseSurfaceHolder mSurfaceHolder = new BaseSurfaceHolder() {
             {
                 mRequestedFormat = PixelFormat.RGBX_8888;
@@ -902,7 +905,7 @@ public abstract class WallpaperService extends Service {
                             View.VISIBLE, 0, -1, mWinFrame, mContentInsets,
                             mVisibleInsets, mStableInsets, mBackdropFrame,
                             mDisplayCutout, mMergedConfiguration, mSurfaceControl,
-                            mInsetsState, mSurfaceSize);
+                            mInsetsState, mSurfaceSize, mTmpSurfaceControl);
                     if (mSurfaceControl.isValid()) {
                         mSurfaceHolder.mSurface.copyFrom(mSurfaceControl);
                         mSurfaceControl.release();
diff --git a/core/java/android/view/IWindowSession.aidl b/core/java/android/view/IWindowSession.aidl
index e3446e1f7b57..1677357dedbe 100644
--- a/core/java/android/view/IWindowSession.aidl
+++ b/core/java/android/view/IWindowSession.aidl
@@ -92,6 +92,9 @@ interface IWindowSession {
      * @param outSurface Object in which is placed the new display surface.
      * @param insetsState The current insets state in the system.
      * @param outSurfaceSize The width and height of the surface control
+     * @param outBlastSurfaceControl A BLAST SurfaceControl allocated by the WindowManager
+     * the SurfaceControl willl be managed by the client side, but the WindowManager
+     * may use it as a deferTransaction barrier.
      *
      * @return int Result flags: {@link WindowManagerGlobal#RELAYOUT_SHOW_FOCUS},
      * {@link WindowManagerGlobal#RELAYOUT_FIRST_TIME}.
@@ -103,7 +106,8 @@ interface IWindowSession {
             out Rect outBackdropFrame,
             out DisplayCutout.ParcelableWrapper displayCutout,
             out MergedConfiguration outMergedConfiguration, out SurfaceControl outSurfaceControl,
-            out InsetsState insetsState, out Point outSurfaceSize);
+            out InsetsState insetsState, out Point outSurfaceSize,
+            out SurfaceControl outBlastSurfaceControl);
 
     /*
      * Notify the window manager that an application is relaunching and
diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index 7a93dcc9e4ec..fbcc261a956e 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -507,7 +507,7 @@ public final class ViewRootImpl implements ViewParent,
     @UnsupportedAppUsage
     public final Surface mSurface = new Surface();
     private final SurfaceControl mSurfaceControl = new SurfaceControl();
-    private SurfaceControl mBlastSurfaceControl;
+    private SurfaceControl mBlastSurfaceControl = new SurfaceControl();
 
     private BLASTBufferQueue mBlastBufferQueue;
 
@@ -1690,23 +1690,17 @@ public final class ViewRootImpl implements ViewParent,
                     .build();
             setBoundsLayerCrop();
             mTransaction.show(mBoundsLayer).apply();
-        }
-        return mBoundsLayer;
+        } 
+       return mBoundsLayer;
     }
 
     Surface getOrCreateBLASTSurface(int width, int height) {
         if (mSurfaceControl == null || !mSurfaceControl.isValid()) {
             return null;
         }
-        if (mBlastSurfaceControl == null) {
-            mBlastSurfaceControl = new SurfaceControl.Builder(mSurfaceSession)
-            .setParent(mSurfaceControl)
-            .setName("BLAST")
-            .setBLASTLayer()
-            .build();
+        if ((mBlastBufferQueue != null) && mBlastSurfaceControl.isValid()) {
             mBlastBufferQueue = new BLASTBufferQueue(
                 mBlastSurfaceControl, width, height);
-
         }
         mBlastBufferQueue.update(mBlastSurfaceControl, width, height);
 
@@ -7344,7 +7338,8 @@ public final class ViewRootImpl implements ViewParent,
                 insetsPending ? WindowManagerGlobal.RELAYOUT_INSETS_PENDING : 0, frameNumber,
                 mTmpFrame, mPendingContentInsets, mPendingVisibleInsets,
                 mPendingStableInsets, mPendingBackDropFrame, mPendingDisplayCutout,
-                mPendingMergedConfiguration, mSurfaceControl, mTempInsets, mSurfaceSize);
+                mPendingMergedConfiguration, mSurfaceControl, mTempInsets, mSurfaceSize,
+                mBlastSurfaceControl);
         if (mSurfaceControl.isValid()) {
             if (!WindowManagerGlobal.USE_BLAST_ADAPTER) {
                 mSurface.copyFrom(mSurfaceControl);
diff --git a/core/java/android/view/WindowlessWindowManager.java b/core/java/android/view/WindowlessWindowManager.java
index 9f2784889cab..91778aaf51fd 100644
--- a/core/java/android/view/WindowlessWindowManager.java
+++ b/core/java/android/view/WindowlessWindowManager.java
@@ -161,7 +161,7 @@ public class WindowlessWindowManager implements IWindowSession {
             Rect outStableInsets, Rect outBackdropFrame,
             DisplayCutout.ParcelableWrapper cutout, MergedConfiguration mergedConfiguration,
             SurfaceControl outSurfaceControl, InsetsState outInsetsState,
-            Point outSurfaceSize) {
+            Point outSurfaceSize, SurfaceControl outBLASTSurfaceControl) {
         State state = null;
         synchronized (this) {
             state = mStateForWindow.get(window.asBinder());