code: public Observable<OperationStatusResponseInner> beginConvertToManagedDisksAsync(String resourceGroupName, String vmName) {
          return beginConvertToManagedDisksWithServiceResponseAsync(resourceGroupName, vmName).map(new Func1<ServiceResponse<OperationStatusResponseInner>, OperationStatusResponseInner>() {
              @Override
              public OperationStatusResponseInner call(ServiceResponse<OperationStatusResponseInner> response) {
                  return response.body();
              }
          });
      }
docs: Converts virtual machine disks from blob-based to managed disks. Virtual machine must be stop-deallocated before invoking this operation.
  
  @param resourceGroupName The name of the resource group.
  @param vmName The name of the virtual machine.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the OperationStatusResponseInner object