Make it possible to custom-paint without an Element.

sky/engine/core/painting/Canvas.cpp

Index: sky/engine/core/painting/Canvas.cpp
diff --git a/sky/engine/core/painting/PaintingContext.cpp b/sky/engine/core/painting/Canvas.cpp
similarity index 55%
copy from sky/engine/core/painting/PaintingContext.cpp
copy to sky/engine/core/painting/Canvas.cpp
index 0bac4898e52ba248bbd421c8bbed01ef0073a218..5e25baf4893daf35302066caabb6bb74ca24b369 100644
--- a/sky/engine/core/painting/PaintingContext.cpp
+++ b/sky/engine/core/painting/Canvas.cpp
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 #include "sky/engine/config.h"
-#include "sky/engine/core/painting/PaintingContext.h"
+#include "sky/engine/core/painting/PictureRecorder.h"
 
 #include "sky/engine/core/dom/Document.h"
 #include "sky/engine/core/dom/Element.h"
@@ -13,24 +13,18 @@
 
 namespace blink {
 
-PassRefPtr<PaintingContext> PaintingContext::create(PassRefPtr<Element> element, const FloatSize& size)
-{
-    return adoptRef(new PaintingContext(element, size));
-}
-
-PaintingContext::PaintingContext(PassRefPtr<Element> element, const FloatSize& size)
-    : m_element(element)
-    , m_size(size)
+Canvas::Canvas(const FloatSize& size)
+    : m_size(size)
 {
     m_displayList = adoptRef(new DisplayList);
     m_canvas = m_displayList->beginRecording(expandedIntSize(m_size));
 }
 
-PaintingContext::~PaintingContext()
+Canvas::~Canvas()
 {
 }
 
-void PaintingContext::drawCircle(double x, double y, double radius, Paint* paint)
+void Canvas::drawCircle(double x, double y, double radius, Paint* paint)
 {
     if (!m_canvas)
         return;
@@ -39,14 +33,13 @@ void PaintingContext::drawCircle(double x, double y, double radius, Paint* paint
     m_canvas->drawCircle(x, y, radius, paint->paint());
 }
 
-void PaintingContext::commit()
+PassRefPtr<DisplayList> Canvas::finishRecording()
 {
-    if (!m_canvas)
-        return;
-    m_displayList->endRecording();
+    if (!isRecording())
+        return nullptr;
     m_canvas = nullptr;
-    PaintingTasks::enqueueCommit(m_element, m_displayList.release());
-    m_element->document().scheduleVisualUpdate();
+    m_displayList->endRecording();
+    return m_displayList.release();
 }
 
 } // namespace blink