Add mechanism for a task's windows to be trusted overlays (SF)

- Add a layer state to indicate that this layer and its children
  in the hierarchy are trusted. This can only be set by callers
  holding ACCESS_SURFACE_FLINGER, and will be used for the PIP
  task layer to indicate that activities in PIP are trusted (as
  they are controlled only by the user and SystemUI)

Bug: 191529039
Test: TBD

Change-Id: Id92ccb087bd0d8dbaeeef3ba50b67fe015e53db8
diff --git a/services/surfaceflinger/SurfaceInterceptor.h b/services/surfaceflinger/SurfaceInterceptor.h
index 30aca83..673f9e7 100644
--- a/services/surfaceflinger/SurfaceInterceptor.h
+++ b/services/surfaceflinger/SurfaceInterceptor.h
@@ -177,6 +177,7 @@
     void addRelativeParentLocked(Transaction* transaction, int32_t layerId, int32_t parentId,
                                  int z);
     void addShadowRadiusLocked(Transaction* transaction, int32_t layerId, float shadowRadius);
+    void addTrustedOverlayLocked(Transaction* transaction, int32_t layerId, bool isTrustedOverlay);
 
     // Add display transactions to the trace
     DisplayChange* createDisplayChangeLocked(Transaction* transaction, int32_t sequenceId);