Hook up CSSPaintValue::image to CSS Paint API callback.

third_party/WebKit/Source/core/css/CSSPaintValue.h

 // Copyright 2016 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.
 
 #ifndef CSSPaintValue_h
 #define CSSPaintValue_h
 
 #include "core/css/CSSCustomIdentValue.h"
 #include "core/css/CSSImageGeneratorValue.h"
+#include "core/css/CSSPaintImageGenerator.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
 class CSSPaintValue : public CSSImageGeneratorValue {
 public:
     static CSSPaintValue* create(CSSCustomIdentValue* name)
     {
         return new CSSPaintValue(name);
     }
@@ skipping 12 matching lines @@
 
     void loadSubimages(Document*) { }
 
     bool equals(const CSSPaintValue&) const;
 
     DECLARE_TRACE_AFTER_DISPATCH();
 
 private:
     explicit CSSPaintValue(CSSCustomIdentValue* name);
 
+    class Observer final : public CSSPaintImageGenerator::Observer {
+        DISALLOW_NEW();
+    public:
+        explicit Observer(CSSPaintValue* ownerValue)
+            : m_ownerValue(ownerValue)
+        {
+        }
+
+        ~Observer() override { }
+        DEFINE_INLINE_TRACE()
+        {
+            visitor->trace(m_ownerValue);
+        }
+
+        void paintImageGeneratorReady() final;
+    private:
+        Member<CSSPaintValue> m_ownerValue;
+    };
+
+    void paintImageGeneratorReady();
+
     Member<CSSCustomIdentValue> m_name;
+    Member<CSSPaintImageGenerator> m_generator;
+    Observer m_paintImageGeneratorObserver;

[haraken, 2016/04/08 04:31:19]

How about just making CSSPaintValue CSSPaintImageGenerator::Observer instead of
introducing a dedicated Observer class?

[ikilpatrick, 2016/04/08 18:43:21]

CSSPaintValue inherits from CSSValue which is a traceAfterDispatch class (no
vtable).

I don't think I can make CSSPaintValue inherit from Observer due to this? I.e.
in TRACE would need cast to CSSValue?

 };
 
 DEFINE_CSS_VALUE_TYPE_CASTS(CSSPaintValue, isPaintValue());
 
 } // namespace blink
 
 #endif // CSSPaintValue_h