Fix problems with flakes in SVG LayoutTests by reordering arithmetic.

Source/core/svg/SVGLengthContext.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.
  * Copyright (C) Research In Motion Limited 2011. 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 34 matching lines @@
 {
     RefPtrWillBeRawPtr<SVGLength> x = passX;
     RefPtrWillBeRawPtr<SVGLength> y = passY;
     RefPtrWillBeRawPtr<SVGLength> width = passWidth;
     RefPtrWillBeRawPtr<SVGLength> height = passHeight;
 
     ASSERT(type != SVGUnitTypes::SVG_UNIT_TYPE_UNKNOWN);
     if (type != SVGUnitTypes::SVG_UNIT_TYPE_USERSPACEONUSE && !viewport.isEmpty()) {
         const FloatSize& viewportSize = viewport.size();
         return FloatRect(
-            convertValueFromPercentageToUserUnits(x->valueAsPercentage(), x->unitMode(), viewportSize) + viewport.x(),
-            convertValueFromPercentageToUserUnits(y->valueAsPercentage(), y->unitMode(), viewportSize) + viewport.y(),
-            convertValueFromPercentageToUserUnits(width->valueAsPercentage(), width->unitMode(), viewportSize),
-            convertValueFromPercentageToUserUnits(height->valueAsPercentage(), height->unitMode(), viewportSize));
+            convertValueFromPercentageToUserUnits(*x, viewportSize) + viewport.x(),
+            convertValueFromPercentageToUserUnits(*y, viewportSize) + viewport.y(),
+            convertValueFromPercentageToUserUnits(*width, viewportSize),
+            convertValueFromPercentageToUserUnits(*height, viewportSize));
     }
 
     SVGLengthContext lengthContext(context);
     return FloatRect(x->value(lengthContext), y->value(lengthContext), width->value(lengthContext), height->value(lengthContext));
 }
 
 FloatPoint SVGLengthContext::resolvePoint(const SVGElement* context, SVGUnitTypes::SVGUnitType type, PassRefPtrWillBeRawPtr<SVGLength> passX, PassRefPtrWillBeRawPtr<SVGLength> passY)
 {
     RefPtrWillBeRawPtr<SVGLength> x = passX;
     RefPtrWillBeRawPtr<SVGLength> y = passY;
@@ skipping 26 matching lines @@
 {
     switch (fromUnit) {
     case LengthTypeUnknown:
         exceptionState.throwDOMException(NotSupportedError, ExceptionMessages::argumentNullOrIncorrectType(3, "SVGLengthType"));
         return 0;
     case LengthTypeNumber:
         return value;
     case LengthTypePX:
         return value;
     case LengthTypePercentage:
-        return convertValueFromPercentageToUserUnits(value / 100, mode, exceptionState);
+        return convertValueFromPercentageToUserUnits(value, mode, exceptionState) / 100;
     case LengthTypeEMS:
         return convertValueFromEMSToUserUnits(value, exceptionState);
     case LengthTypeEXS:
         return convertValueFromEXSToUserUnits(value, exceptionState);
     case LengthTypeCM:
         return value * cssPixelsPerCentimeter;
     case LengthTypeMM:
         return value * cssPixelsPerMillimeter;
     case LengthTypeIN:
         return value * cssPixelsPerInch;
@@ skipping 72 matching lines @@
 
 float SVGLengthContext::convertValueFromPercentageToUserUnits(float value, SVGLengthMode mode, const FloatSize& viewportSize)
 {
     switch (mode) {
     case LengthModeWidth:
         return value * viewportSize.width();
     case LengthModeHeight:
         return value * viewportSize.height();
     case LengthModeOther:
         return value * sqrtf(viewportSize.diagonalLengthSquared() / 2);
-    };
+    }
 
     ASSERT_NOT_REACHED();
     return 0;
+}
+
+float SVGLengthContext::convertValueFromPercentageToUserUnits(const SVGLength& value, const FloatSize& viewportSize)
+{
+    switch (value.unitMode()) {
+    case LengthModeWidth:
+        return value.scaleByPercentage(viewportSize.width());
+    case LengthModeHeight:
+        return value.scaleByPercentage(viewportSize.height());
+    case LengthModeOther:
+        return value.scaleByPercentage(sqrtf(viewportSize.diagonalLengthSquared() / 2));
+    }
+
+    ASSERT_NOT_REACHED();
+    return 0;
 }
 
 static inline RenderStyle* renderStyleForLengthResolving(const SVGElement* context)
 {
     if (!context)
         return 0;
 
     const ContainerNode* currentContext = context;
     do {
         if (currentContext->renderer())
@@ skipping 84 matching lines @@
 
     const SVGSVGElement& svg = toSVGSVGElement(*viewportElement);
     viewportSize = svg.currentViewBoxRect().size();
     if (viewportSize.isEmpty())
         viewportSize = svg.currentViewportSize();
 
     return true;
 }
 
 }