Convert fast/multicol/positioned-split to reftest.

LayoutTests/platform/win/fast/multicol/positioned-split-expected.txt

Index: LayoutTests/platform/win/fast/multicol/positioned-split-expected.txt
diff --git a/LayoutTests/platform/win/fast/multicol/positioned-split-expected.txt b/LayoutTests/platform/win/fast/multicol/positioned-split-expected.txt
deleted file mode 100644
index d45f9e36b4ccfad31f5cc829ca2723da851bb489..0000000000000000000000000000000000000000
--- a/LayoutTests/platform/win/fast/multicol/positioned-split-expected.txt
+++ /dev/null
@@ -1,26 +0,0 @@
-layer at (0,0) size 800x600
-  RenderView at (0,0) size 800x600
-layer at (0,0) size 800x600
-  RenderBlock {HTML} at (0,0) size 800x600
-    RenderBody {BODY} at (8,8) size 784x584
-layer at (8,8) size 784x304
-  RenderBlock {DIV} at (0,0) size 784x304 [border: (2px solid #000000)]
-    RenderBlock {DIV} at (2,2) size 382x250
-    RenderBlock {DIV} at (2,252) size 382x250
-layer at (10,260) size 300x200
-  RenderBlock (positioned) {DIV} at (0,0) size 300x200 [bgcolor=#D3D3D3]
-    RenderText {#text} at (0,0) size 292x17
-      text run at (0,0) width 292: "This text should paginate across the columns."
-    RenderBR {BR} at (291,14) size 1x0
-    RenderText {#text} at (0,18) size 292x17
-      text run at (0,18) width 292: "This text should paginate across the columns."
-    RenderBR {BR} at (291,32) size 1x0
-    RenderText {#text} at (0,50) size 292x17
-      text run at (0,50) width 292: "This text should paginate across the columns."
-    RenderBR {BR} at (291,64) size 1x0
-    RenderText {#text} at (0,68) size 292x17
-      text run at (0,68) width 292: "This text should paginate across the columns."
-    RenderBR {BR} at (291,82) size 1x0
-    RenderText {#text} at (0,86) size 292x17
-      text run at (0,86) width 292: "This text should paginate across the columns."
-    RenderBR {BR} at (291,100) size 1x0