[sf] populate snashot path for legacy frontend

Provide a consistent way for middleend/backend to identify
mirrored or cloned layers.

Test: presubmit
Bug: 258231640
Change-Id: Id7cbadf1e581b9420859ddff024e9ce101b28e95
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index a538c6d..aa832f6 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -2561,7 +2561,10 @@
     return outputLayer ? outputLayer->getState().visibleRegion : Region();
 }
 
-void Layer::setInitialValuesForClone(const sp<Layer>& clonedFrom) {
+void Layer::setInitialValuesForClone(const sp<Layer>& clonedFrom, uint32_t mirrorRootId) {
+    mSnapshot->path.id = clonedFrom->getSequence();
+    mSnapshot->path.mirrorRootId = mirrorRootId;
+
     cloneDrawingState(clonedFrom.get());
     mClonedFrom = clonedFrom;
     mPremultipliedAlpha = clonedFrom->mPremultipliedAlpha;
@@ -2662,7 +2665,7 @@
         }
         sp<Layer> clonedChild = clonedLayersMap[child];
         if (clonedChild == nullptr) {
-            clonedChild = child->createClone();
+            clonedChild = child->createClone(mirrorRoot->getSequence());
             clonedLayersMap[child] = clonedChild;
         }
         addChildToDrawing(clonedChild);
@@ -3478,11 +3481,11 @@
     }
 }
 
-sp<Layer> Layer::createClone() {
+sp<Layer> Layer::createClone(uint32_t mirrorRootId) {
     LayerCreationArgs args(mFlinger.get(), nullptr, mName + " (Mirror)", 0, LayerMetadata());
     args.textureName = mTextureName;
     sp<Layer> layer = mFlinger->getFactory().createBufferStateLayer(args);
-    layer->setInitialValuesForClone(sp<Layer>::fromExisting(this));
+    layer->setInitialValuesForClone(sp<Layer>::fromExisting(this), mirrorRootId);
     return layer;
 }