Consider text alignment and direction when computing the left offset for horizontal writing modes.

Source/core/rendering/RenderBoxModelObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 2644 matching lines @@
     // However, as soon as some content is entered, the line boxes will be
     // constructed and this kludge is not called any more. So only the caret size
     // of an empty :first-line'd block is wrong. I think we can live with that.
     RenderStyle* currentStyle = firstLineStyle();
     LayoutUnit height = lineHeight(true, currentStyle->isHorizontalWritingMode() ? HorizontalLine : VerticalLine,  PositionOfInteriorLineBoxes);
 
     enum CaretAlignment { alignLeft, alignRight, alignCenter };
 
     CaretAlignment alignment = alignLeft;
 
-    switch (currentStyle->textAlign()) {
+    switch (simplifiedTextAlign(currentStyle->textAlign())) {
     case LEFT:
-    case WEBKIT_LEFT:
         break;
     case CENTER:
-    case WEBKIT_CENTER:
         alignment = alignCenter;
         break;
     case RIGHT:
-    case WEBKIT_RIGHT:
         alignment = alignRight;
         break;
     case JUSTIFY:
-    case TASTART:
         if (!currentStyle->isLeftToRightDirection())
             alignment = alignRight;
         break;
-    case TAEND:
-        if (currentStyle->isLeftToRightDirection())
-            alignment = alignRight;
+    default:
+        ASSERT_NOT_REACHED();
         break;
     }
 
     LayoutUnit x = borderLeft() + paddingLeft();
     LayoutUnit maxX = width - borderRight() - paddingRight();
 
     switch (alignment) {
     case alignLeft:
         if (currentStyle->isLeftToRightDirection())
             x += textIndentOffset;
@@ skipping 135 matching lines @@
     ASSERT(!beforeChild || toBoxModelObject == beforeChild->parent());
     for (RenderObject* child = startChild; child && child != endChild; ) {
         // Save our next sibling as moveChildTo will clear it.
         RenderObject* nextSibling = child->nextSibling();
         moveChildTo(toBoxModelObject, child, beforeChild, fullRemoveInsert);
         child = nextSibling;
     }
 }
 
 } // namespace WebCore