Emit dummy display item when recorded picture is empty

Source/platform/graphics/paint/FilterDisplayItem.h

Index: Source/platform/graphics/paint/FilterDisplayItem.h
diff --git a/Source/platform/graphics/paint/FilterDisplayItem.h b/Source/platform/graphics/paint/FilterDisplayItem.h
index 87424c560adef739fcdc19e974509452eff9948b..2a03b4c0d7eba34caa970406e2a8dc6c1e440767 100644
--- a/Source/platform/graphics/paint/FilterDisplayItem.h
+++ b/Source/platform/graphics/paint/FilterDisplayItem.h
@@ -29,6 +29,7 @@ protected:
 
 private:
 #ifndef NDEBUG
+    virtual const char* name() const override { return "BeginFilter"; }
     virtual void dumpPropertiesAsDebugString(WTF::StringBuilder&) const override;
 #endif
 
@@ -46,6 +47,11 @@ public:
 protected:
     EndFilterDisplayItem(DisplayItemClient client)
         : DisplayItem(client, EndFilter) { }
+
+private:
+#ifndef NDEBUG
+    virtual const char* name() const override { return "EndFilter"; }
+#endif
 };
 
 }