all: replace deprecated pointer.Rect with clip.Rect

Converted with

gofmt -w -r 'pointer.Rect(r) -> clip.Rect(r)' .
gofmt -w -r 'pointer.Ellipse(r) -> clip.Ellipse(layout.FRect(r))' .

combined with 'goimports -w .' to clean up imports.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

widget/material/checkbox.go

@@ -5,8 +5,8 @@ package material
 import (
 	"image"
 
-	"gioui.org/io/pointer"
 	"gioui.org/layout"
+	"gioui.org/op/clip"
 	"gioui.org/unit"
 	"gioui.org/widget"
 )
@@ -35,7 +35,7 @@ func CheckBox(th *Theme, checkBox *widget.Bool, label string) CheckBoxStyle {
 // Layout updates the checkBox and displays it.
 func (c CheckBoxStyle) Layout(gtx layout.Context) layout.Dimensions {
 	dims := c.layout(gtx, c.CheckBox.Value, c.CheckBox.Hovered())
-	defer pointer.Rect(image.Rectangle{Max: dims.Size}).Push(gtx.Ops).Pop()
+	defer clip.Rect(image.Rectangle{Max: dims.Size}).Push(gtx.Ops).Pop()
 	gtx.Constraints.Min = dims.Size
 	c.CheckBox.Layout(gtx)
 	return dims