Add localToAbsoluteTransform and localToAncestorTransform.

third_party/WebKit/Source/platform/geometry/TransformState.h

Index: third_party/WebKit/Source/platform/geometry/TransformState.h
diff --git a/third_party/WebKit/Source/platform/geometry/TransformState.h b/third_party/WebKit/Source/platform/geometry/TransformState.h
index d0ed2753bf62ada0a6adab171e007bd0d8f193cc..8712f8c7f350428bfc2fa23a05d59a677ba61b4c 100644
--- a/third_party/WebKit/Source/platform/geometry/TransformState.h
+++ b/third_party/WebKit/Source/platform/geometry/TransformState.h
@@ -59,6 +59,7 @@ public:
         , m_mapPoint(true)
         , m_mapQuad(false)
         , m_direction(mappingDirection)
+        , m_forceAccumulatingTransform(false)
     {
     }
 
@@ -68,6 +69,18 @@ public:
         , m_mapPoint(false)
         , m_mapQuad(true)
         , m_direction(mappingDirection)
+        , m_forceAccumulatingTransform(false)
+    {
+    }
+
+    // Accumulate a transform but don't map any points directly.
+    TransformState(TransformDirection mappingDirection)
+        : m_accumulatedTransform(TransformationMatrix::create())
+        , m_accumulatingTransform(true)
+        , m_mapPoint(false)
+        , m_mapQuad(false)
+        , m_direction(mappingDirection)
+        , m_forceAccumulatingTransform(true)
     {
     }
 
@@ -106,6 +119,9 @@ public:
     FloatPoint mappedPoint(bool* wasClamped = 0) const;
     FloatQuad mappedQuad(bool* wasClamped = 0) const;
 
+    // Return the accumulated transform.
+    const TransformationMatrix& accumulatedTransform() const;
+
 private:
     void translateTransform(const LayoutSize&);
     void translateMappedCoordinates(const LayoutSize&);
@@ -121,6 +137,7 @@ private:
     bool m_accumulatingTransform;
     bool m_mapPoint, m_mapQuad;
     TransformDirection m_direction;
+    bool m_forceAccumulatingTransform;

[szager1, 2016/03/08 23:34:15]

Please reorder to keep all the bool's together.

[dmazzoni, 2016/03/09 18:14:59]

Done.

 };
 
 } // namespace blink