Simplify this a bit.
Simplify this a bit.

By taking advantage of 1) cell array being std::vector, and 2) broadcasters
are no longer stored with cells.

Change-Id: I9ba1d3004e62d7bb7810d8fed0c4e8fd17605d0f

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core