Create native Surface object on updateWindow for legacy apps.

There are some apps that use the Surface object itself to indicate
changes. As a result, recycling the existing Surface object for
updates can lead to such apps ignoring events such as size changes.

This changelist restores the original behavior for legacy apps, where
the underlying native Surface object is recreated during updates.

Fixes: 62108743
Test: go/wm-smoke
Test: Open affected application, observe expansion to fullscreen when
      nav bar disappears. Rotate to other orientation and observe
      expansion to fullscreen.

Change-Id: I874602b6b8686c6ecb05cf7b1a04ec4b700ad3f9

3 files changed, 60 insertions, 1 deletions

diff --git a/core/java/android/view/Surface.java b/core/java/android/view/Surface.java
index 8bb3fa988a45..4f9dbd5ad7a0 100644
--- a/core/java/android/view/Surface.java
+++ b/core/java/android/view/Surface.java
@@ -52,7 +52,9 @@ public class Surface implements Parcelable {
 
     private static native long nativeCreateFromSurfaceTexture(SurfaceTexture surfaceTexture)
             throws OutOfResourcesException;
+
     private static native long nativeCreateFromSurfaceControl(long surfaceControlNativeObject);
+    private static native long nativeGetFromSurfaceControl(long surfaceControlNativeObject);
 
     private static native long nativeLockCanvas(long nativeObject, Canvas canvas, Rect dirty)
             throws OutOfResourcesException;
@@ -410,6 +412,9 @@ public class Surface implements Parcelable {
      * back from a client, converting it from the representation being managed
      * by the window manager to the representation the client uses to draw
      * in to it.
+     *
+     * @param other {@link SurfaceControl} to copy from.
+     *
      * @hide
      */
     public void copyFrom(SurfaceControl other) {
@@ -420,7 +425,39 @@ public class Surface implements Parcelable {
         long surfaceControlPtr = other.mNativeObject;
         if (surfaceControlPtr == 0) {
             throw new NullPointerException(
-                    "SurfaceControl native object is null. Are you using a released SurfaceControl?");
+                    "null SurfaceControl native object. Are you using a released SurfaceControl?");
+        }
+        long newNativeObject = nativeGetFromSurfaceControl(surfaceControlPtr);
+
+        synchronized (mLock) {
+            if (mNativeObject != 0) {
+                nativeRelease(mNativeObject);
+            }
+            setNativeObjectLocked(newNativeObject);
+        }
+    }
+
+    /**
+     * Gets a reference a surface created from this one.  This surface now holds a reference
+     * to the same data as the original surface, and is -not- the owner.
+     * This is for use by the window manager when returning a window surface
+     * back from a client, converting it from the representation being managed
+     * by the window manager to the representation the client uses to draw
+     * in to it.
+     *
+     * @param other {@link SurfaceControl} to create surface from.
+     *
+     * @hide
+     */
+    public void createFrom(SurfaceControl other) {
+        if (other == null) {
+            throw new IllegalArgumentException("other must not be null");
+        }
+
+        long surfaceControlPtr = other.mNativeObject;
+        if (surfaceControlPtr == 0) {
+            throw new NullPointerException(
+                    "null SurfaceControl native object. Are you using a released SurfaceControl?");
         }
         long newNativeObject = nativeCreateFromSurfaceControl(surfaceControlPtr);
 
diff --git a/core/java/android/view/SurfaceView.java b/core/java/android/view/SurfaceView.java
index 679a9cd92bc2..34ceeb7bcc0d 100644
--- a/core/java/android/view/SurfaceView.java
+++ b/core/java/android/view/SurfaceView.java
@@ -641,6 +641,16 @@ public class SurfaceView extends View implements ViewRootImpl.WindowStoppedCallb
                         mSurface.copyFrom(mSurfaceControl);
                     }
 
+                    if (getContext().getApplicationInfo().targetSdkVersion
+                            < Build.VERSION_CODES.O) {
+                        // Some legacy applications use the underlying native {@link Surface} object
+                        // as a key to whether anything has changed. In these cases, updates to the
+                        // existing {@link Surface} will be ignored when the size changes.
+                        // Therefore, we must explicitly recreate the {@link Surface} in these
+                        // cases.
+                        mSurface.createFrom(mSurfaceControl);
+                    }
+
                     if (visible && mSurface.isValid()) {
                         if (!mSurfaceCreated && (surfaceChanged || visibleChanged)) {
                             mSurfaceCreated = true;
diff --git a/core/jni/android_view_Surface.cpp b/core/jni/android_view_Surface.cpp
index 5839fd50d79a..7744e0cd6b5d 100644
--- a/core/jni/android_view_Surface.cpp
+++ b/core/jni/android_view_Surface.cpp
@@ -394,6 +394,16 @@ static void nativeAllocateBuffers(JNIEnv* /* env */ , jclass /* clazz */,
 
 static jlong nativeCreateFromSurfaceControl(JNIEnv* env, jclass clazz,
         jlong surfaceControlNativeObj) {
+    sp<SurfaceControl> ctrl(reinterpret_cast<SurfaceControl *>(surfaceControlNativeObj));
+    sp<Surface> surface(ctrl->createSurface());
+    if (surface != NULL) {
+        surface->incStrong(&sRefBaseOwner);
+    }
+    return reinterpret_cast<jlong>(surface.get());
+}
+
+static jlong nativeGetFromSurfaceControl(JNIEnv* env, jclass clazz,
+        jlong surfaceControlNativeObj) {
     /*
      * This is used by the WindowManagerService just after constructing
      * a Surface and is necessary for returning the Surface reference to
@@ -590,6 +600,8 @@ static const JNINativeMethod gSurfaceMethods[] = {
             (void*)nativeAllocateBuffers },
     {"nativeCreateFromSurfaceControl", "(J)J",
             (void*)nativeCreateFromSurfaceControl },
+    {"nativeGetFromSurfaceControl", "(J)J",
+            (void*)nativeGetFromSurfaceControl },
     {"nativeReadFromParcel", "(JLandroid/os/Parcel;)J",
             (void*)nativeReadFromParcel },
     {"nativeWriteToParcel", "(JLandroid/os/Parcel;)V",