Merge "[RpcSession] Add checks before setting SessionSpecificRoot" into main

Author: Alice Wang

libs/binder/RpcSession.cpp

@@ -802,6 +802,10 @@ bool RpcSession::setForServer(const wp<RpcServer>& server, const wp<EventListene
 }
 
 void RpcSession::setSessionSpecificRoot(const sp<IBinder>& sessionSpecificRoot) {
+    LOG_ALWAYS_FATAL_IF(mSessionSpecificRootObject != nullptr,
+                        "Session specific root object already set");
+    LOG_ALWAYS_FATAL_IF(mForServer != nullptr,
+                        "Session specific root object cannot be set for a server");
     mSessionSpecificRootObject = sessionSpecificRoot;
 }