Simplify flattening to just write enough to call the factory

include/core/SkFlattenable.h

Index: include/core/SkFlattenable.h
diff --git a/include/core/SkFlattenable.h b/include/core/SkFlattenable.h
index f6d377a9d743b4838f6e2e6206053f0056729bee..4b90e2e1916f649ee96bce6de0394e6fe64b4814 100644
--- a/include/core/SkFlattenable.h
+++ b/include/core/SkFlattenable.h
@@ -1,4 +1,3 @@
-
 /*
  * Copyright 2006 The Android Open Source Project
  *
@@ -6,12 +5,13 @@
  * found in the LICENSE file.
  */
 
-
 #ifndef SkFlattenable_DEFINED
 #define SkFlattenable_DEFINED
 
 #include "SkRefCnt.h"
 
+//#define SK_SUPPORT_LEGACY_DEEPFLATTENING
+
 class SkReadBuffer;
 class SkWriteBuffer;
 
@@ -30,11 +30,25 @@ class SkWriteBuffer;
 #define SK_DECLARE_UNFLATTENABLE_OBJECT() \
     virtual Factory getFactory() const SK_OVERRIDE { return NULL; }
 
-#define SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(flattenable) \
-    virtual Factory getFactory() const SK_OVERRIDE { return CreateProc; } \
-    static SkFlattenable* CreateProc(SkReadBuffer& buffer) { \
-        return SkNEW_ARGS(flattenable, (buffer)); \
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
+#define SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(flattenable)    \
+    static SkFlattenable* CreateProc(SkReadBuffer&);                        \
+    virtual Factory getFactory() const SK_OVERRIDE {return DeepCreateProc;} \
+    static SkFlattenable* DeepCreateProc(SkReadBuffer& buffer) {            \
+        if (NeedsDeepUnflatten(buffer)) {                                   \
+            return SkNEW_ARGS(flattenable, (buffer));                       \
+        }                                                                   \
+        return CreateProc(buffer);                                          \
     }
+#else
+#define SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(flattenable)    \
+    static SkFlattenable* CreateProc(SkReadBuffer&);                        \
+    virtual Factory getFactory() const SK_OVERRIDE { return CreateProc; }
+#endif
+
+// If your subclass will *never* need to be unflattened, declar this.
+#define SK_DECLARE_NOT_FLATTENABLE_PROCS(flattenable)   \
+    virtual Factory getFactory() const SK_OVERRIDE { return ReturnNullCreateProc; }
 
 /** For SkFlattenable derived objects with a valid type
     This macro should only be used in base class objects in core
@@ -101,7 +115,17 @@ public:
     virtual void flatten(SkWriteBuffer&) const;
 
 protected:
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
+    enum {
+        kNewFlattenVersion = 27
+    };
+    static bool NeedsDeepUnflatten(const SkReadBuffer&);
     SkFlattenable(SkReadBuffer&) {}
+#endif
+
+    static SkFlattenable* ReturnNullCreateProc(SkReadBuffer&) {
+        return NULL;
+    }
 
 private:
     static void InitializeFlattenablesIfNeeded();