Have BidiRunList destructor delete runs

Source/core/rendering/RenderBlockLineLayout.cpp

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All right 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 802 matching lines @@
         bool isNewUBAParagraph = layoutState.lineInfo().previousLineBrokeCleanly();
         FloatingObject* lastFloatFromPreviousLine = (containsFloats()) ? m_floatingObjects->set().last().get() : 0;
 
         WordMeasurements wordMeasurements;
         endOfLine = lineBreaker.nextLineBreak(resolver, bidiRuns,
             layoutState.lineInfo(), renderTextInfo,
             lastFloatFromPreviousLine, wordMeasurements);
         renderTextInfo.m_lineBreakIterator.resetPriorContext();
         if (resolver.position().atEnd()) {
             // FIXME: We shouldn't be creating any runs in nextLineBreak to begin with!
-            // Once BidiRunList is separated from BidiResolver this will not be needed.
+            // Figure out why we create new runs in nextLineBreak and why we
+            // seem to rely on that behavior.
+            // Removing the addRun calls in LineBreaker::skipLeadingWhitespace
+            // breaks a bunch of bidi layout tests.
             bidiRuns.deleteRuns();
             resolver.markCurrentRunEmpty(); // FIXME: This can probably be replaced by an ASSERT (or just removed).
             layoutState.setCheckForFloatsFromLastLine(true);
             resolver.setPosition(InlineIterator(resolver.position().root(), 0, 0), 0);
             break;
         }
 
         ASSERT(endOfLine != resolver.position());
 
         // This is a short-cut for empty lines.
@@ skipping 1200 matching lines @@
     float logicalLeft = logicalLeftOffsetForLine(logicalHeight(), false).toFloat();
     float availableLogicalWidth = logicalRightOffsetForLine(logicalHeight(), false) - logicalLeft;
     updateLogicalWidthForAlignment(textAlign, 0, 0, logicalLeft, totalLogicalWidth, availableLogicalWidth, 0);
 
     if (!style()->isLeftToRightDirection())
         return logicalWidth() - logicalLeft;
     return logicalLeft;
 }
 
 }