code: public void setReconciliationSource(com.google.api.ads.admanager.axis.v201805.BillFrom reconciliationSource) {
          this.reconciliationSource = reconciliationSource;
      }
docs: Sets the reconciliationSource value for this ReconciliationLineItemReport.
  
  @param reconciliationSource   * Specifies which of {@link #dfpVolume}, {@link #thirdPartyVolume},
  or {@link #manualVolume}
  should be used as the {@link #reconciledVolume}.
  The value is optional. If this reconciliation data
  is for a {@link ProposalLineItem} then
  this will default to the proposal line item's {@link
  ProposalLineItem#billingSource}.
  Otherwise, this will default to {@link BillFrom#DFP}.