SVG doesn't recognize ch units.

Source/core/svg/SVGLength.cpp

 /*
  * Copyright (C) 2004, 2005, 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Apple 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 45 matching lines @@
     case LengthTypeMM:
         return "mm";
     case LengthTypeIN:
         return "in";
     case LengthTypePT:
         return "pt";
     case LengthTypePC:
         return "pc";
     case LengthTypeREMS:
         return "rem";
+    case LengthTypeCHS:
+        return "ch";
     }
 
     ASSERT_NOT_REACHED();
     return "";
 }
 
 template<typename CharType>
 SVGLengthType stringToLengthType(const CharType*& ptr, const CharType* end)
 {
     if (ptr == end)
@@ skipping 20 matching lines @@
             if (secondChar == 'm')
                 type = LengthTypeEMS;
             if (secondChar == 'x')
                 type = LengthTypeEXS;
         } else if (firstChar == 'r') {
             if (secondChar == 'e' && ptr < end) {
                 const CharType thirdChar = *ptr++;
                 if (thirdChar == 'm')
                     type = LengthTypeREMS;
             }
-        } else if (firstChar == 'c' && secondChar == 'm') {
-            type = LengthTypeCM;
+        } else if (firstChar == 'c') {
+            if (secondChar == 'h')
+                type = LengthTypeCHS;
+            if (secondChar == 'm')
+                type = LengthTypeCM;
         } else if (firstChar == 'm' && secondChar == 'm') {
             type = LengthTypeMM;
         } else if (firstChar == 'i' && secondChar == 'n') {
             type = LengthTypeIN;
         } else if (isHTMLSpace<CharType>(firstChar) && isHTMLSpace<CharType>(secondChar)) {
             type = LengthTypeNumber;
         }
     }
 
     if (!skipOptionalSVGSpaces(ptr, end))
@@ skipping 186 matching lines @@
         break;
     case CSSPrimitiveValue::CSS_IN:
         svgType = LengthTypeIN;
         break;
     case CSSPrimitiveValue::CSS_PT:
         svgType = LengthTypePT;
         break;
     case CSSPrimitiveValue::CSS_REMS:
         svgType = LengthTypeREMS;
         break;
+    case CSSPrimitiveValue::CSS_CHS:
+        svgType = LengthTypeCHS;
+        break;
     default:
         ASSERT(value->primitiveType() == CSSPrimitiveValue::CSS_PC);
         svgType = LengthTypePC;
         break;
     };
 
     RefPtrWillBeRawPtr<SVGLength> length = SVGLength::create();
     length->newValueSpecifiedUnits(svgType, value->getFloatValue());
     return length.release();
 }
@@ skipping 32 matching lines @@
         break;
     case LengthTypePT:
         cssType = CSSPrimitiveValue::CSS_PT;
         break;
     case LengthTypePC:
         cssType = CSSPrimitiveValue::CSS_PC;
         break;
     case LengthTypeREMS:
         cssType = CSSPrimitiveValue::CSS_REMS;
         break;
+    case LengthTypeCHS:
+        cssType = CSSPrimitiveValue::CSS_CHS;
+        break;
     };
 
     return CSSPrimitiveValue::create(length->valueInSpecifiedUnits(), cssType);
 }
 
 SVGLengthMode SVGLength::lengthModeForAnimatedLengthAttribute(const QualifiedName& attrName)
 {
     typedef HashMap<QualifiedName, SVGLengthMode> LengthModeForLengthAttributeMap;
     DEFINE_STATIC_LOCAL(LengthModeForLengthAttributeMap, s_lengthModeMap, ());
 
@@ skipping 33 matching lines @@
 {
     RefPtrWillBeRawPtr<SVGLength> from = passFrom;
 
     SVGLengthType toType = unitType();
     SVGLengthType fromType = from->unitType();
     if ((from->isZero() && isZero())
         || fromType == LengthTypeUnknown
         || toType == LengthTypeUnknown
         || (!from->isZero() && fromType != LengthTypePercentage && toType == LengthTypePercentage)
         || (!isZero() && fromType == LengthTypePercentage && toType != LengthTypePercentage)
-        || (!from->isZero() && !isZero() && (fromType == LengthTypeEMS || fromType == LengthTypeEXS || fromType == LengthTypeREMS) && fromType != toType))
+        || (!from->isZero() && !isZero() && (fromType == LengthTypeEMS || fromType == LengthTypeEXS || fromType == LengthTypeREMS || fromType == LengthTypeCHS) && fromType != toType))
         return clone();
 
     RefPtrWillBeRawPtr<SVGLength> length = create();
 
     if (fromType == LengthTypePercentage || toType == LengthTypePercentage) {
         float fromPercent = from->valueAsPercentage100();
         float toPercent = valueAsPercentage100();
         length->newValueSpecifiedUnits(LengthTypePercentage, blink::blend(fromPercent, toPercent, progress));
         return length;
     }
 
-    if (fromType == toType || from->isZero() || isZero() || fromType == LengthTypeEMS || fromType == LengthTypeEXS || fromType == LengthTypeREMS) {
+    if (fromType == toType || from->isZero() || isZero() || fromType == LengthTypeEMS || fromType == LengthTypeEXS || fromType == LengthTypeREMS || fromType == LengthTypeCHS) {
         float fromValue = from->valueInSpecifiedUnits();
         float toValue = valueInSpecifiedUnits();
         if (isZero())
             length->newValueSpecifiedUnits(fromType, blink::blend(fromValue, toValue, progress));
         else
             length->newValueSpecifiedUnits(toType, blink::blend(fromValue, toValue, progress));
         return length;
     }
 
     ASSERT(!isRelative());
@@ skipping 31 matching lines @@
 
 float SVGLength::calculateDistance(PassRefPtrWillBeRawPtr<SVGPropertyBase> toValue, SVGElement* contextElement)
 {
     SVGLengthContext lengthContext(contextElement);
     RefPtrWillBeRawPtr<SVGLength> toLength = toSVGLength(toValue);
 
     return fabsf(toLength->value(lengthContext) - value(lengthContext));
 }
 
 }