Merge "libbinder: RPC reject excess threads"

sp<RpcSession::RpcConnection> RpcSession::assignIncomingConnectionToThisThread(unique_fd fd) {

    std::lock_guard<std::mutex> _l(mMutex);

    if (mIncomingConnections.size() >= mMaxThreads) {

        ALOGE("Cannot add thread to session with %zu threads (max is set to %zu)",

              mIncomingConnections.size(), mMaxThreads);

        return nullptr;

    }

    // Don't accept any more connections, some have shutdown. Usually this

    // happens when new connections are still being established as part of a

    // very short-lived session which shuts down after it already started