Convert fast/multicol/single-line into a reftest.

LayoutTests/platform/win/fast/multicol/single-line-expected.txt

Index: LayoutTests/platform/win/fast/multicol/single-line-expected.txt
diff --git a/LayoutTests/platform/win/fast/multicol/single-line-expected.txt b/LayoutTests/platform/win/fast/multicol/single-line-expected.txt
deleted file mode 100644
index 41853357fa88181954d2d1d8854cc49b95cfa0ce..0000000000000000000000000000000000000000
--- a/LayoutTests/platform/win/fast/multicol/single-line-expected.txt
+++ /dev/null
@@ -1,42 +0,0 @@
-layer at (0,0) size 800x600
-  RenderView at (0,0) size 800x600
-layer at (0,0) size 800x286
-  RenderBlock {HTML} at (0,0) size 800x286
-    RenderBody {BODY} at (8,16) size 784x254
-      RenderBlock {P} at (0,0) size 784x18
-        RenderText {#text} at (0,0) size 780x17
-          text run at (0,0) width 397: "This test checks if CSS3 multi-column layout properly works "
-          text run at (396,0) width 384: "when the multi-column block contains only one line of text."
-      RenderBlock {P} at (0,34) size 784x18
-        RenderText {#text} at (0,0) size 571x17
-          text run at (0,0) width 306: "Test successful if the following text is readable "
-          text run at (305,0) width 266: "(i.e. not split into two different columns)."
-      RenderBlock {DIV} at (0,236) size 784x18
-layer at (8,84) size 784x18
-  RenderBlock {P} at (0,68) size 784x18 [bgcolor=#EEEEEE]
-    RenderText {#text} at (0,0) size 67x17
-      text run at (0,0) width 67: "Short text."
-layer at (8,118) size 784x34
-  RenderBlock {P} at (0,102) size 784x34 [bgcolor=#EEEEEE]
-    RenderInline {SPAN} at (0,0) size 142x33
-      RenderText {#text} at (0,0) size 142x33
-        text run at (0,0) width 142: "Bigger text."
-    RenderText {#text} at (0,0) size 0x0
-layer at (8,168) size 784x34
-  RenderBlock {P} at (0,152) size 784x34 [bgcolor=#EEEEEE]
-    RenderText {#text} at (0,13) size 59x17
-      text run at (0,13) width 59: "Partially "
-    RenderInline {SPAN} at (0,0) size 39x33
-      RenderText {#text} at (58,0) size 39x33
-        text run at (58,0) width 39: "big"
-    RenderText {#text} at (96,13) size 33x17
-      text run at (96,13) width 33: " text."
-layer at (8,218) size 784x18
-  RenderBlock {DIV} at (0,202) size 784x18 [bgcolor=#EEEEEE]
-    RenderBlock {P} at (0,16) size 184x20
-      RenderText {#text} at (0,2) size 88x17
-        text run at (0,2) width 88: "Nested block."
-layer at (8,252) size 784x18
-  RenderBlock {P} at (0,0) size 784x18 [bgcolor=#EEEEEE]
-    RenderText {#text} at (0,0) size 108x17
-      text run at (0,0) width 108: "Nested block #2."