Remove the "horizontal-bt" value from -webkit-writing-mode

third_party/WebKit/LayoutTests/css3/flexbox/flex-flow-orientations.html

Index: third_party/WebKit/LayoutTests/css3/flexbox/flex-flow-orientations.html
diff --git a/third_party/WebKit/LayoutTests/css3/flexbox/flex-flow-orientations.html b/third_party/WebKit/LayoutTests/css3/flexbox/flex-flow-orientations.html
index 8b513e1e0fc6c0a63248ec5ab32f0341ccca4f9e..ec67f42f3c7fc47035d5c667f82aca7db1e5699a 100644
--- a/third_party/WebKit/LayoutTests/css3/flexbox/flex-flow-orientations.html
+++ b/third_party/WebKit/LayoutTests/css3/flexbox/flex-flow-orientations.html
@@ -28,9 +28,6 @@
 .horizontal-tb {
     -webkit-writing-mode: horizontal-tb;
 }
-.horizontal-bt {
-    -webkit-writing-mode: horizontal-bt;
-}
 .vertical-rl {
     -webkit-writing-mode: vertical-rl;
 }
@@ -87,24 +84,6 @@ var expectations = {
             ltr: [[80, 0], [60, 0]]
         }
     },
-    'horizontal-bt': {
-        column: {
-            rtl: [[80, 80], [80, 60]],
-            ltr: [[0, 80], [0, 60]]
-        },
-        'column-reverse': {
-            rtl: [[80, 0], [80, 20]],
-            ltr: [[0, 0], [0, 20]]
-        },
-        row: {
-            rtl: [[80, 80], [60, 80]],
-            ltr: [[0, 80], [20, 80]]
-        },
-        'row-reverse': {
-            rtl: [[0, 80], [20, 80]],
-            ltr: [[80, 80], [60, 80]]
-        }
-    },
     'vertical-lr': {
         column: {
             rtl: [[0, 80], [20, 80]],
@@ -143,26 +122,10 @@ var expectations = {
     }
 };
 
-var writingModes = ['horizontal-tb', 'horizontal-bt', 'vertical-lr', 'vertical-rl'];
+var writingModes = ['horizontal-tb', 'vertical-lr', 'vertical-rl'];
 var flexFlows = ['row', 'column', 'row-reverse', 'column-reverse'];
 var directions = ['rtl', 'ltr'];
 
-function physicalWritingMode(writingMode, flexFlow, direction)
-{
-    if (flexFlow.indexOf('column') == -1)
-        return writingMode;
-
-    var isReverse = flexFlow.indexOf('reverse') != -1;
-    switch (writingMode) {
-    case 'horizontal-tb':
-    case 'horizontal-bt':
-        return isReverse ? 'vertical-rl' : 'vertical-lr';
-    case 'vertical-lr':
-    case 'vertical-rl':
-        return isReverse ? 'horizontal-bt' : 'horizontal-tb';
-    }
-}
-
 writingModes.forEach(function(writingMode) {
     flexFlows.forEach(function(flexFlow) {
         directions.forEach(function(direction) {