[Oilpan] Prepare full definition of classes before using Member

third_party/WebKit/Source/platform/graphics/filters/Filter.h

Index: third_party/WebKit/Source/platform/graphics/filters/Filter.h
diff --git a/third_party/WebKit/Source/platform/graphics/filters/Filter.h b/third_party/WebKit/Source/platform/graphics/filters/Filter.h
index a89510d7a13cf58d046a2c2cee009965f54e9eb4..576e41204730dc647710e956f1ba593daa9e2e92 100644
--- a/third_party/WebKit/Source/platform/graphics/filters/Filter.h
+++ b/third_party/WebKit/Source/platform/graphics/filters/Filter.h
@@ -25,12 +25,12 @@
 #include "platform/geometry/FloatPoint3D.h"
 #include "platform/geometry/FloatRect.h"
 #include "platform/geometry/IntRect.h"
+#include "platform/graphics/filters/SourceGraphic.h"
 #include "platform/heap/Handle.h"
 #include "wtf/RefCounted.h"
 
 namespace blink {
 
-class SourceGraphic;
 class FilterEffect;
 
 class PLATFORM_EXPORT Filter final : public RefCountedWillBeGarbageCollectedFinalized<Filter> {
@@ -61,7 +61,7 @@ public:
     const FloatRect& referenceBox() const { return m_referenceBox; }
 
     void setLastEffect(PassRefPtrWillBeRawPtr<FilterEffect>);
-    FilterEffect* lastEffect() const { return m_lastEffect.get(); }
+    FilterEffect* lastEffect() const;
 
     SourceGraphic* sourceGraphic() const { return m_sourceGraphic.get(); }