Move and rename RenderBR to LayoutBR.

LayoutTests/platform/mac/css1/box_properties/clear-expected.txt

Index: LayoutTests/platform/mac/css1/box_properties/clear-expected.txt
diff --git a/LayoutTests/platform/mac/css1/box_properties/clear-expected.txt b/LayoutTests/platform/mac/css1/box_properties/clear-expected.txt
index a8cbaf42fb33a28fb34c18d97890dce0a555080c..b364cb6c36aed080f320ccc5c78945878f15a817 100644
--- a/LayoutTests/platform/mac/css1/box_properties/clear-expected.txt
+++ b/LayoutTests/platform/mac/css1/box_properties/clear-expected.txt
@@ -22,19 +22,19 @@ layer at (0,0) size 785x961 backgroundClip at (0,0) size 785x600 clip at (0,0) s
         RenderText {#text} at (18,0) size 607x18
           text run at (18,0) width 607: "This text should be flowing past a tall orange rectangle on the left side of the browser window."
       RenderBlock (anonymous) at (0,159) size 769x18
-        RenderBR {BR} at (18,0) size 0x18
+        LayoutBR {BR} at (18,0) size 0x18
         LayoutImage {IMG} at (0,18) size 15x50
       RenderBlock {P} at (0,227) size 769x18
         RenderText {#text} at (0,0) size 662x18
           text run at (0,0) width 662: "This paragraph should appear below the tall orange rectangle above and to the left, and not flow past it."
       RenderBlock (anonymous) at (0,261) size 769x18
-        RenderBR {BR} at (0,0) size 0x18
+        LayoutBR {BR} at (0,0) size 0x18
         LayoutImage {IMG} at (754,18) size 15x50
       RenderBlock {P} at (0,329) size 769x18
         RenderText {#text} at (0,0) size 671x18
           text run at (0,0) width 671: "This paragraph should appear below the tall orange rectangle above and to the right, and not flow past it."
       RenderBlock (anonymous) at (0,363) size 769x18
-        RenderBR {BR} at (0,0) size 0x18
+        LayoutBR {BR} at (0,0) size 0x18
         LayoutImage {IMG} at (0,18) size 15x50
         LayoutImage {IMG} at (754,18) size 15x50
       RenderBlock {P} at (0,431) size 769x18
@@ -46,7 +46,7 @@ layer at (0,0) size 785x961 backgroundClip at (0,0) size 785x600 clip at (0,0) s
         RenderText {#text} at (18,0) size 397x18
           text run at (18,0) width 397: "This paragraph should be between both tall orange rectangles."
       RenderBlock (anonymous) at (0,499) size 769x18
-        RenderBR {BR} at (18,0) size 0x18
+        LayoutBR {BR} at (18,0) size 0x18
       LayoutTable {TABLE} at (0,517) size 693x428 [border: (1px outset #808080)]
         LayoutTableSection {TBODY} at (1,1) size 691x426
           LayoutTableRow {TR} at (0,0) size 691x26
@@ -64,19 +64,19 @@ layer at (0,0) size 785x961 backgroundClip at (0,0) size 785x600 clip at (0,0) s
                 RenderText {#text} at (18,0) size 607x18
                   text run at (18,0) width 607: "This text should be flowing past a tall orange rectangle on the left side of the browser window."
               RenderBlock (anonymous) at (4,38) size 671x18
-                RenderBR {BR} at (18,0) size 0x18
+                LayoutBR {BR} at (18,0) size 0x18
                 LayoutImage {IMG} at (0,18) size 15x50
               RenderBlock {P} at (4,106) size 671x18
                 RenderText {#text} at (0,0) size 662x18
                   text run at (0,0) width 662: "This paragraph should appear below the tall orange rectangle above and to the left, and not flow past it."
               RenderBlock (anonymous) at (4,140) size 671x18
-                RenderBR {BR} at (0,0) size 0x18
+                LayoutBR {BR} at (0,0) size 0x18
                 LayoutImage {IMG} at (656,18) size 15x50
               RenderBlock {P} at (4,208) size 671x18
                 RenderText {#text} at (0,0) size 671x18
                   text run at (0,0) width 671: "This paragraph should appear below the tall orange rectangle above and to the right, and not flow past it."
               RenderBlock (anonymous) at (4,242) size 671x18
-                RenderBR {BR} at (0,0) size 0x18
+                LayoutBR {BR} at (0,0) size 0x18
                 LayoutImage {IMG} at (0,18) size 15x50
                 LayoutImage {IMG} at (656,18) size 15x50
               RenderBlock {P} at (4,310) size 671x18
@@ -88,4 +88,4 @@ layer at (0,0) size 785x961 backgroundClip at (0,0) size 785x600 clip at (0,0) s
                 RenderText {#text} at (18,0) size 397x18
                   text run at (18,0) width 397: "This paragraph should be between both tall orange rectangles."
               RenderBlock (anonymous) at (4,378) size 671x18
-                RenderBR {BR} at (18,0) size 0x18
+                LayoutBR {BR} at (18,0) size 0x18