Fixed theme bg color missing spots

README.md

@@ -82,7 +82,6 @@ Feel free to add a new one. You can use 256 colors, bold, underline, and reverse
     - zooming in and out of graphs
     - add gif
     - gopsutil issue for darwin i386
-    - grid should create a filled buffer so that bg is written everywhere
 * cleaning up code
     - termui Blocks should ignore writing to the outside area
         - Ignore writes to outside of inner area, or give error?

termui/grid.go

@@ -44,7 +44,7 @@ func (g *Grid) Resize() {
 
 // Buffer implements Bufferer interface.
 func (g *Grid) Buffer() *Buffer {
-	buf := NewBuffer()
+	buf := NewFilledBuffer(0, 0, g.Width, g.Height, Cell{' ', ColorDefault, Theme.Bg})
 	for _, w := range g.Widgets {
 		buf.MergeWithOffset(w.Buffer(), w.GetXOffset(), w.GetYOffset())
 	}