Simplify flattening to just write enough to call the factory

src/effects/SkComposeImageFilter.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkComposeImageFilter.h"
 #include "SkReadBuffer.h"
@@ skipping 35 matching lines @@
 
     if (!outer || !inner) {
         return (outer ? outer : inner)->filterBounds(src, ctm, dst);
     }
 
     SkIRect tmp;
     return inner->filterBounds(src, ctm, &tmp) &&
            outer->filterBounds(tmp, ctm, dst);
 }
 
+SkFlattenable* SkComposeImageFilter::CreateProc(SkReadBuffer& buffer) {
+    Common common;
+    if (!common.unflatten(buffer)) {
+        return NULL;
+    }
+    switch (common.inputCount()) {
+        case 1:
+            return SkRef(common.inputs()[0]);
+        case 2:
+            return SkComposeImageFilter::Create(common.inputs()[0], common.inputs()[1]);
+        default:
+            return NULL;
+    }
+}
+
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
 SkComposeImageFilter::SkComposeImageFilter(SkReadBuffer& buffer)
   : INHERITED(2, buffer) {
 }
+#endif