will-change on SVG elements should not reset transforms.

Source/core/css/resolver/StyleAdjuster.cpp

Index: Source/core/css/resolver/StyleAdjuster.cpp
diff --git a/Source/core/css/resolver/StyleAdjuster.cpp b/Source/core/css/resolver/StyleAdjuster.cpp
index 733e50a61fb46c2684ba9ef0e8434d79e1581285..bde89655e5b0c883de11f1d9566610b60db48fd6 100644
--- a/Source/core/css/resolver/StyleAdjuster.cpp
+++ b/Source/core/css/resolver/StyleAdjuster.cpp
@@ -197,7 +197,9 @@ void StyleAdjuster::adjustComputedStyle(ComputedStyle& style, const ComputedStyl
 
     // will-change:transform should result in the same rendering behavior as having a transform,
     // including the creation of a containing block for fixed position descendants.
-    if (!style.hasTransform() && (style.willChangeProperties().contains(CSSPropertyWebkitTransform) || style.willChangeProperties().contains(CSSPropertyTransform))) {
+    // can skip this because they implicitly have transforms.

[pdr., 2015/04/11 17:04:25]

Almost there but this is still not correct. Please read my first reply more
carefully. You'll need to add the words "SVG elements" to the previous line so
this is a complete sentence.

+    bool isSVGElement = e && e->isSVGElement();
+    if (!isSVGElement && !style.hasTransform() && (style.willChangeProperties().contains(CSSPropertyWebkitTransform) || style.willChangeProperties().contains(CSSPropertyTransform))) {
         bool makeIdentity = true;
         style.setTransform(TransformOperations(makeIdentity));
     }
@@ -228,7 +230,7 @@ void StyleAdjuster::adjustComputedStyle(ComputedStyle& style, const ComputedStyl
         || style.hasFilter()))
         style.setTransformStyle3D(TransformStyle3DFlat);
 
-    if (e && e->isSVGElement()) {
+    if (isSVGElement) {
         // Only the root <svg> element in an SVG document fragment tree honors css position
         if (!(isSVGSVGElement(*e) && e->parentNode() && !e->parentNode()->isSVGElement()))
             style.setPosition(ComputedStyle::initialPosition());