Set write buffer flags only in SkWriteBuffer and SkFlatController constructors.

src/core/SkPictureFlat.h

Index: src/core/SkPictureFlat.h
diff --git a/src/core/SkPictureFlat.h b/src/core/SkPictureFlat.h
index 431fa960370b00b4dab52670734b86c599587fa1..7973e65398188d720fd06db7fedcb25512a3a438 100644
--- a/src/core/SkPictureFlat.h
+++ b/src/core/SkPictureFlat.h
@@ -168,7 +168,7 @@ class SkFlatController : public SkRefCnt {
 public:
     SK_DECLARE_INST_COUNT(SkFlatController)
 
-    SkFlatController();
+    SkFlatController(uint32_t writeBufferFlags = 0);
     virtual ~SkFlatController();
     /**
      * Return a new block of memory for the SkFlatDictionary to use.
@@ -242,17 +242,12 @@ protected:
      */
     SkNamedFactorySet* setNamedFactorySet(SkNamedFactorySet*);
 
-    /**
-     * Set the flags to be used during flattening.
-     */
-    void setWriteBufferFlags(uint32_t flags) { fWriteBufferFlags = flags; }
-
 private:
     SkBitmapHeap*       fBitmapHeap;
     SkRefCntSet*        fTypefaceSet;
     SkTypefacePlayback* fTypefacePlayback;
     SkNamedFactorySet*  fFactorySet;
-    uint32_t            fWriteBufferFlags;
+    const uint32_t      fWriteBufferFlags;
 
     typedef SkRefCnt INHERITED;
 };
@@ -264,12 +259,11 @@ public:
     static SkFlatData* Create(SkFlatController* controller, const T& obj, int index) {
         // A buffer of 256 bytes should fit most paints, regions, and matrices.
         uint32_t storage[64];
-        SkWriteBuffer buffer(storage, sizeof(storage));
+        SkWriteBuffer buffer(storage, sizeof(storage), controller->getWriteBufferFlags());
 
         buffer.setBitmapHeap(controller->getBitmapHeap());
         buffer.setTypefaceRecorder(controller->getTypefaceSet());
         buffer.setNamedFactoryRecorder(controller->getNamedFactorySet());
-        buffer.setFlags(controller->getWriteBufferFlags());
 
         Traits::flatten(buffer, obj);
         size_t size = buffer.bytesWritten();
@@ -367,6 +361,7 @@ class SkFlatDictionary {
 public:
     explicit SkFlatDictionary(SkFlatController* controller)
     : fController(SkRef(controller))
+    , fScratch(controller->getWriteBufferFlags())
     , fReady(false) {
         this->reset();
     }
@@ -496,7 +491,6 @@ private:
         fScratch.setBitmapHeap(fController->getBitmapHeap());
         fScratch.setTypefaceRecorder(fController->getTypefaceSet());
         fScratch.setNamedFactoryRecorder(fController->getNamedFactorySet());
-        fScratch.setFlags(fController->getWriteBufferFlags());
         fReady = true;
     }