Merge "When not provided set viewerConfigInputStreamProvider from viewerConfigFilePath" into main

        // NOTE: Registering that datasource is an async operation, so there may be no data traced

        // for some messages logged right after the construction of this class.

        mDataSource.register(params);

        if (viewerConfigInputStreamProvider == null && viewerConfigFilePath != null) {

            viewerConfigInputStreamProvider = new ViewerConfigInputStreamProvider() {

                @NonNull

                @Override

                public ProtoInputStream getInputStream() {

                    try {

                        return new ProtoInputStream(new FileInputStream(viewerConfigFilePath));

                    } catch (FileNotFoundException e) {

                        throw new RuntimeException(

                                "Failed to load viewer config file " + viewerConfigFilePath, e);

                    }

                }

            };

        }

        this.mViewerConfigInputStreamProvider = viewerConfigInputStreamProvider;

        this.mViewerConfigReader = viewerConfigReader;

        this.mCacheUpdater = cacheUpdater;