Background image should clamp to minimum size(1, 1) after scale.

LayoutTests/platform/linux/fast/backgrounds/size/zero-expected.txt

Index: LayoutTests/platform/linux/fast/backgrounds/size/zero-expected.txt
diff --git a/LayoutTests/platform/linux/fast/backgrounds/size/zero-expected.txt b/LayoutTests/platform/linux/fast/backgrounds/size/zero-expected.txt
index c61a1431bd6934da098147e3ae59c060397517ff..64d8b6dca9cbfcf18b78beb24c5b907150ba7cb8 100644
--- a/LayoutTests/platform/linux/fast/backgrounds/size/zero-expected.txt
+++ b/LayoutTests/platform/linux/fast/backgrounds/size/zero-expected.txt
@@ -14,10 +14,11 @@ layer at (0,0) size 800x600
             text run at (550,0) width 29: " Bug"
         RenderText {#text} at (579,0) size 4x19
           text run at (579,0) width 4: "."
-      RenderBlock {P} at (0,36) size 784x20
-        RenderText {#text} at (0,0) size 548x19
-          text run at (0,0) width 548: "There should be four empty squares with black borders. WebKit should not hang or assert."
-      RenderBlock {DIV} at (8,72) size 106x106 [border: (3px solid #000000)]
-      RenderBlock {DIV} at (8,186) size 106x106 [border: (3px solid #000000)]
-      RenderBlock {DIV} at (8,300) size 106x106 [border: (3px solid #000000)]
-      RenderBlock {DIV} at (8,414) size 106x106 [border: (3px solid #000000)]
+      RenderBlock {P} at (0,36) size 784x40
+        RenderText {#text} at (0,0) size 772x39
+          text run at (0,0) width 772: "There should be three empty squares with black borders and the last one should have blue background. WebKit should not hang"
+          text run at (0,20) width 56: "or assert."
+      RenderBlock {DIV} at (8,92) size 106x106 [border: (3px solid #000000)]
+      RenderBlock {DIV} at (8,206) size 106x106 [border: (3px solid #000000)]
+      RenderBlock {DIV} at (8,320) size 106x106 [border: (3px solid #000000)]
+      RenderBlock {DIV} at (8,434) size 106x106 [border: (3px solid #000000)]