Move and rename RenderBR to LayoutBR.

LayoutTests/platform/win/tables/mozilla/bugs/bug20804-expected.txt

Index: LayoutTests/platform/win/tables/mozilla/bugs/bug20804-expected.txt
diff --git a/LayoutTests/platform/win/tables/mozilla/bugs/bug20804-expected.txt b/LayoutTests/platform/win/tables/mozilla/bugs/bug20804-expected.txt
index 6682def53bc1c89f19055d7bff5851a8faea0db5..1d0a3affd720aec0ee5e63f5ce571add02192819 100644
--- a/LayoutTests/platform/win/tables/mozilla/bugs/bug20804-expected.txt
+++ b/LayoutTests/platform/win/tables/mozilla/bugs/bug20804-expected.txt
@@ -9,10 +9,10 @@ layer at (0,0) size 800x600
         RenderInline {A} at (0,0) size 171x17 [color=#0000EE]
           RenderText {#text} at (149,0) size 171x17
             text run at (149,0) width 171: "http://www.microsoft.com"
-        RenderBR {BR} at (319,14) size 1x0
+        LayoutBR {BR} at (319,14) size 1x0
         RenderText {#text} at (0,18) size 596x17
           text run at (0,18) width 596: "The problem seems to be that the last cell in each row have an \"excessive\" COLSPAN value."
-        RenderBR {BR} at (595,32) size 1x0
+        LayoutBR {BR} at (595,32) size 1x0
         RenderText {#text} at (0,36) size 399x17
           text run at (0,36) width 399: "I have added BORDER=1 to make the cell boundaries visible."
       LayoutTable {TABLE} at (0,70) size 784x86 [border: (1px outset #808080)]
@@ -46,7 +46,7 @@ layer at (0,0) size 800x600
       RenderBlock {P} at (0,172) size 784x36
         RenderText {#text} at (0,0) size 660x17
           text run at (0,0) width 660: "The following table is exactly as above, but I have removed COLSPAN for the last cell in row 1 and 2,"
-        RenderBR {BR} at (659,14) size 1x0
+        LayoutBR {BR} at (659,14) size 1x0
         RenderText {#text} at (0,18) size 384x17
           text run at (0,18) width 384: "and changed COLSPAN=4 to COLSPAN=3 in the last row."
       LayoutTable {TABLE} at (0,224) size 784x86 [border: (1px outset #808080)]