Simplify flattening to just write enough to call the factory

include/effects/Sk2DPathEffect.h

Index: include/effects/Sk2DPathEffect.h
diff --git a/include/effects/Sk2DPathEffect.h b/include/effects/Sk2DPathEffect.h
index 2adf598012c355934d443329e4a002cfcaa33300..b0d0cacec11e841fb631e329743204e81b505d5f 100644
--- a/include/effects/Sk2DPathEffect.h
+++ b/include/effects/Sk2DPathEffect.h
@@ -44,7 +44,9 @@ protected:
 
     // protected so that subclasses can call this during unflattening
     explicit Sk2DPathEffect(const SkMatrix& mat);
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
     explicit Sk2DPathEffect(SkReadBuffer&);
+#endif
     virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
 
 private:
@@ -73,7 +75,9 @@ public:
 protected:
     SkLine2DPathEffect(SkScalar width, const SkMatrix& matrix)
         : Sk2DPathEffect(matrix), fWidth(width) {}
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
     explicit SkLine2DPathEffect(SkReadBuffer&);
+#endif
 
     virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
 
@@ -99,7 +103,9 @@ public:
 
 protected:
     SkPath2DPathEffect(const SkMatrix&, const SkPath&);
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
     explicit SkPath2DPathEffect(SkReadBuffer& buffer);
+#endif
     virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
 
     virtual void next(const SkPoint&, int u, int v, SkPath*) const SK_OVERRIDE;