Fix incorrect handling of small non-percentage value for 'startOffset' on <textPath>

third_party/WebKit/Source/core/layout/svg/SVGTextLayoutEngine.cpp

 /*
  * Copyright (C) Research In Motion Limited 2010-2012. 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 154 matching lines @@
 void SVGTextLayoutEngine::beginTextPathLayout(SVGInlineFlowBox* flowBox)
 {
     // Build text chunks for all <textPath> children, using the line layout algorithm.
     // This is needeed as text-anchor is just an additional startOffset for text paths.
     SVGTextLayoutEngine lineLayout(m_layoutAttributes);
     lineLayout.m_textLengthSpacingInEffect = m_textLengthSpacingInEffect;
     lineLayout.layoutCharactersInTextBoxes(flowBox);
 
     m_inPathLayout = true;
     LayoutSVGTextPath* textPath = &toLayoutSVGTextPath(flowBox->layoutObject());
-
     Path path = textPath->layoutPath();
     if (path.isEmpty())
         return;
     m_textPathCalculator = new Path::PositionCalculator(path);
     m_textPathStartOffset = textPath->startOffset();
     m_textPathLength = path.length();
-    if (m_textPathStartOffset > 0 && m_textPathStartOffset <= 1)
+    if (textPath->isPercentageForStartOffset()

[fs, 2016/01/18 12:57:49]

I'd suggest that you instead pass m_textPathLength to startOffset() and do the
computation/resolution within that function. It'd probably be better to let
SVGLengthContext be able to handle this, but that would require some
refactoring.

+        && m_textPathStartOffset > 0 && m_textPathStartOffset <= 1)
         m_textPathStartOffset *= m_textPathLength;
 
     SVGTextPathChunkBuilder textPathChunkLayoutBuilder;
     textPathChunkLayoutBuilder.processTextChunks(lineLayout.m_lineLayoutBoxes);
 
     m_textPathStartOffset += textPathChunkLayoutBuilder.totalTextAnchorShift();
     m_textPathCurrentOffset = m_textPathStartOffset;
 
     // Eventually handle textLength adjustments.
     SVGLengthAdjustType lengthAdjust = SVGLengthAdjustUnknown;
@@ skipping 359 matching lines @@
     }
 
     if (!didStartTextFragment)
         return;
 
     // Close last open fragment, if needed.
     recordTextFragment(textBox);
 }
 
 }