Move and rename RenderBR to LayoutBR.

LayoutTests/platform/win/css3/flexbox/button-expected.txt

Index: LayoutTests/platform/win/css3/flexbox/button-expected.txt
diff --git a/LayoutTests/platform/win/css3/flexbox/button-expected.txt b/LayoutTests/platform/win/css3/flexbox/button-expected.txt
index e5df3ae293256a7ac3bf3bb68ebfe6c3a8ea08b3..f46f98bd4c6c6bd15f08cc4fe5a529e78c5c3b36 100644
--- a/LayoutTests/platform/win/css3/flexbox/button-expected.txt
+++ b/LayoutTests/platform/win/css3/flexbox/button-expected.txt
@@ -17,19 +17,19 @@ layer at (0,0) size 800x252
       RenderBlock (anonymous) at (0,54) size 784x59
         RenderText {#text} at (0,0) size 81x17
           text run at (0,0) width 81: "Simple case."
-        RenderBR {BR} at (80,0) size 1x17
+        LayoutBR {BR} at (80,0) size 1x17
         RenderButton {BUTTON} at (0,29) size 16x6 [bgcolor=#C0C0C0] [border: (2px outset #C0C0C0)]
-        RenderBR {BR} at (16,18) size 0x17
+        LayoutBR {BR} at (16,18) size 0x17
         RenderButton {INPUT} at (0,36) size 16x22 [bgcolor=#C0C0C0] [border: (2px outset #C0C0C0)]
-        RenderBR {BR} at (16,41) size 0x17
+        LayoutBR {BR} at (16,41) size 0x17
       RenderBlock {HR} at (0,121) size 784x2 [border: (1px inset #EEEEEE)]
       RenderBlock (anonymous) at (0,131) size 784x105
         RenderText {#text} at (0,0) size 745x35
           text run at (0,0) width 745: "Empty <button> and <input type=button> with overflow: scroll;. The presence of the scrollbar should not shrink the"
           text run at (0,18) width 45: "button."
-        RenderBR {BR} at (44,18) size 1x17
-        RenderBR {BR} at (31,36) size 0x17
-        RenderBR {BR} at (31,73) size 0x17
+        LayoutBR {BR} at (44,18) size 1x17
+        LayoutBR {BR} at (31,36) size 0x17
+        LayoutBR {BR} at (31,73) size 0x17
 layer at (8,186) size 31x21 clip at (10,188) size 12x2
   RenderButton {BUTTON} at (0,47) size 31x21 [bgcolor=#C0C0C0] [border: (2px outset #C0C0C0)]
 layer at (8,207) size 31x37 clip at (10,209) size 12x18