Add a transform paint property for local SVG transforms

third_party/WebKit/Source/core/paint/ObjectPaintProperties.h

Index: third_party/WebKit/Source/core/paint/ObjectPaintProperties.h
diff --git a/third_party/WebKit/Source/core/paint/ObjectPaintProperties.h b/third_party/WebKit/Source/core/paint/ObjectPaintProperties.h
index cb8ad1b4b0e012d51b88fe50998370354cdb82be..5e1bce72725843dce576acef80a2df29350c55a6 100644
--- a/third_party/WebKit/Source/core/paint/ObjectPaintProperties.h
+++ b/third_party/WebKit/Source/core/paint/ObjectPaintProperties.h
@@ -27,6 +27,8 @@ class ObjectPaintProperties {
 public:
     struct LocalBorderBoxProperties;
 
+    // TODO(pdr): This should be refactored to not pass 11 arguments because it
+    // is hard to follow here and at the callsites.
     static PassOwnPtr<ObjectPaintProperties> create(
         PassRefPtr<TransformPaintPropertyNode> paintOffsetTranslation,
         PassRefPtr<TransformPaintPropertyNode> transform,
@@ -35,11 +37,15 @@ public:
         PassRefPtr<ClipPaintPropertyNode> cssClipFixedPosition,
         PassRefPtr<ClipPaintPropertyNode> overflowClip,
         PassRefPtr<TransformPaintPropertyNode> perspective,
+        PassRefPtr<TransformPaintPropertyNode> svgLocalTransform,
         PassRefPtr<TransformPaintPropertyNode> scrollTranslation,
         PassRefPtr<TransformPaintPropertyNode> scrollbarPaintOffset,
         PassOwnPtr<LocalBorderBoxProperties> localBorderBoxProperties)
     {
-        return adoptPtr(new ObjectPaintProperties(paintOffsetTranslation, transform, effect, cssClip, cssClipFixedPosition, overflowClip, perspective, scrollTranslation, scrollbarPaintOffset, localBorderBoxProperties));
+        return adoptPtr(new ObjectPaintProperties(paintOffsetTranslation,
+            transform, effect, cssClip, cssClipFixedPosition, overflowClip,
+            perspective, svgLocalTransform, scrollTranslation,
+            scrollbarPaintOffset, localBorderBoxProperties));
     }
 
     // The hierarchy of transform subtree created by a LayoutObject.
@@ -48,6 +54,7 @@ public:
     // +---[ transform ]                    The space created by CSS transform.
     //     |                                This is the local border box space, see: LocalBorderBoxProperties below.
     //     +---[ perspective ]              The space created by CSS perspective.
+    //     |   +---[ svgLocalTransform ]    The transform for an SVG element.
     //     |   +---[ scrollTranslation ]    The space created by overflow clip.

[jbroman, 2016/04/07 14:37:11]

Can an element have both an SVG local transform and a scroll translation? (If
so, can you confirm that this is the right hierarchy?)

[jbroman, 2016/04/07 18:47:38]

Would you mind clarifying this? The code in question updates the context when it
creates both of them, so if both could be created, then they would be parent and
child, not siblings.

If you don't want to draw it as parent-child, perhaps something like:

   +--[ svgLocalTransform ]
         OR
   +--[ scrollTranslation ]

With a DCHECK after creating both that they don't exist simultaneously, i.e.

DCHECK(!newTransformNodeForSvgLocalTransform ||
!newTransformNodeForScrollTranslation)
    << "SVG elements cannot have scroll translation";

     //     +---[ scrollbarPaintOffset ]     TODO(trchen): Remove this once we bake the paint offset into frameRect.
     //                                      This is equivalent to the local border box space above,
@@ -56,6 +63,7 @@ public:
     TransformPaintPropertyNode* paintOffsetTranslation() const { return m_paintOffsetTranslation.get(); }
     TransformPaintPropertyNode* transform() const { return m_transform.get(); }
     TransformPaintPropertyNode* perspective() const { return m_perspective.get(); }
+    TransformPaintPropertyNode* svgLocalTransform() const { return m_svgLocalTransform.get(); }
     TransformPaintPropertyNode* scrollTranslation() const { return m_scrollTranslation.get(); }
     TransformPaintPropertyNode* scrollbarPaintOffset() const { return m_scrollbarPaintOffset.get(); }
 
@@ -89,6 +97,7 @@ private:
         PassRefPtr<ClipPaintPropertyNode> cssClipFixedPosition,
         PassRefPtr<ClipPaintPropertyNode> overflowClip,
         PassRefPtr<TransformPaintPropertyNode> perspective,
+        PassRefPtr<TransformPaintPropertyNode> svgLocalTransform,
         PassRefPtr<TransformPaintPropertyNode> scrollTranslation,
         PassRefPtr<TransformPaintPropertyNode> scrollbarPaintOffset,
         PassOwnPtr<LocalBorderBoxProperties> localBorderBoxProperties)
@@ -99,6 +108,7 @@ private:
         , m_cssClipFixedPosition(cssClipFixedPosition)
         , m_overflowClip(overflowClip)
         , m_perspective(perspective)
+        , m_svgLocalTransform(svgLocalTransform)
         , m_scrollTranslation(scrollTranslation)
         , m_scrollbarPaintOffset(scrollbarPaintOffset)
         , m_localBorderBoxProperties(localBorderBoxProperties) { }
@@ -110,6 +120,7 @@ private:
     RefPtr<ClipPaintPropertyNode> m_cssClipFixedPosition;
     RefPtr<ClipPaintPropertyNode> m_overflowClip;
     RefPtr<TransformPaintPropertyNode> m_perspective;
+    RefPtr<TransformPaintPropertyNode> m_svgLocalTransform;
     RefPtr<TransformPaintPropertyNode> m_scrollTranslation;
     RefPtr<TransformPaintPropertyNode> m_scrollbarPaintOffset;