Fix #459
Fix #459

Firefox getComputedStyle() in innerDimensions util returns greater than desired width value for 100% width SVG.
Set explicit width instead.

fxcebx/d3fc,alisd23/d3fc-d3v4,janakerman/d3-financial-components,fxcebx/d3fc,bjedrzejewski/d3fc,janakerman/d3-financial-components,djmiley/d3fc,djmiley/d3fc,alisd23/d3fc-d3v4,djmiley/d3fc,bjedrzejewski/d3fc,alisd23/d3fc-d3v4,fxcebx/d3fc,bjedrzejewski/d3fc