Move and rename RenderBR to LayoutBR.

LayoutTests/platform/linux/fast/forms/select-baseline-expected.txt

Index: LayoutTests/platform/linux/fast/forms/select-baseline-expected.txt
diff --git a/LayoutTests/platform/linux/fast/forms/select-baseline-expected.txt b/LayoutTests/platform/linux/fast/forms/select-baseline-expected.txt
index 1c4592e7c570688c18084f6a6cc0c2a5b6e48757..f4707788da4dfe311584190b06d6cbcebb022fdc 100644
--- a/LayoutTests/platform/linux/fast/forms/select-baseline-expected.txt
+++ b/LayoutTests/platform/linux/fast/forms/select-baseline-expected.txt
@@ -5,10 +5,10 @@ layer at (0,0) size 800x600
     RenderBody {BODY} at (8,8) size 784x584
       RenderText {#text} at (0,0) size 444x19
         text run at (0,0) width 444: "This tests that empty select controls and buttons have the correct baseline."
-      RenderBR {BR} at (444,15) size 0x0
+      LayoutBR {BR} at (444,15) size 0x0
       RenderMenuList {SELECT} at (0,21) size 25x20 [bgcolor=#C0C0C0] [border: (1px solid #A9A9A9)]
         RenderBlock (anonymous) at (1,1) size 23x18
-          RenderBR at (4,1) size 0x16 [bgcolor=#C0C0C0]
+          LayoutBR at (4,1) size 0x16 [bgcolor=#C0C0C0]
       RenderText {#text} at (25,21) size 29x19
         text run at (25,21) width 29: " test "
       RenderMenuList {SELECT} at (54,21) size 47x20 [bgcolor=#C0C0C0] [border: (1px solid #A9A9A9)]
@@ -19,7 +19,7 @@ layer at (0,0) size 800x600
         text run at (101,21) width 4: " "
       RenderMenuList {SELECT} at (105,21) size 25x20 [color=#00008B] [bgcolor=#ADD8E6] [border: (1px solid #A9A9A9)]
         RenderBlock (anonymous) at (1,1) size 23x18
-          RenderBR at (4,1) size 0x16 [bgcolor=#ADD8E6]
+          LayoutBR at (4,1) size 0x16 [bgcolor=#ADD8E6]
       RenderText {#text} at (130,21) size 29x19
         text run at (130,21) width 29: " test "
       RenderMenuList {SELECT} at (159,21) size 47x20 [color=#00008B] [bgcolor=#ADD8E6] [border: (1px solid #A9A9A9)]