Canvas.concat takes a 16-element Float32List instead of an array.

sky/engine/core/painting/Canvas.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sky/engine/config.h"
 #include "sky/engine/core/painting/Canvas.h"
 
 #include "sky/engine/core/dom/Document.h"
 #include "sky/engine/core/dom/Element.h"
 #include "sky/engine/core/painting/CanvasImage.h"
@@ skipping 65 matching lines @@
 }
 
 void Canvas::skew(float sx, float sy)
 {
     if (!m_canvas)
         return;
     ASSERT(m_displayList->isRecording());
     m_canvas->skew(sx, sy);
 }
 
-void Canvas::concat(const Vector<float>& matrix)
+void Canvas::concat(const Float32List& matrix4)
 {
     if (!m_canvas)
         return;
     ASSERT(m_displayList->isRecording());
-    ASSERT(matrix.size() == 9);
+    ASSERT(matrix4.data);
+
+    // TODO(mpcomplete): how can we raise an error in this case?
+    if (matrix4.num_elements != 16)
+      return;
+
     SkMatrix sk_matrix;
-    sk_matrix.set9(matrix.data());
+    // Mappings from SkMatrix-index to input-index.
+    static const int kMappings[] = {
+      0, 4, 12,
+      1, 5, 13,
+      3, 7, 15,
+    };
+    for (intptr_t i = 0; i < 9; ++i)
+      sk_matrix[i] = matrix4.data[kMappings[i]];
+
     m_canvas->concat(sk_matrix);
 }
 
 void Canvas::clipRect(const Rect& rect)
 {
     if (!m_canvas)
         return;
     ASSERT(m_displayList->isRecording());
     m_canvas->clipRect(rect.sk_rect);
 }
@@ skipping 67 matching lines @@
 PassRefPtr<DisplayList> Canvas::finishRecording()
 {
     if (!isRecording())
         return nullptr;
     m_canvas = nullptr;
     m_displayList->endRecording();
     return m_displayList.release();
 }
 
 } // namespace blink