More efficient SkRecorder::flushMiniRecorder()

src/core/SkMiniRecorder.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkMiniRecorder_DEFINED
 #define SkMiniRecorder_DEFINED
 
 #include "SkRecords.h"
 #include "SkScalar.h"
 #include "SkTypes.h"
 class SkCanvas;
 
 // Records small pictures, but only a limited subset of the canvas API, and may fail.
 class SkMiniRecorder : SkNoncopyable {
 public:
     SkMiniRecorder();
     ~SkMiniRecorder();
 
     // Try to record an op.  Returns false on failure.
     bool drawPath(const SkPath&, const SkPaint&);
     bool drawRect(const SkRect&, const SkPaint&);
     bool drawTextBlob(const SkTextBlob*, SkScalar x, SkScalar y, const SkPaint&);
 
     // Detach anything we've recorded as a picture, resetting this SkMiniRecorder.
     SkPicture* detachAsPicture(const SkRect& cull);
 
+    // Flush anything we've recorded to the canvas, resetting this SkMiniRecorder.
+    // This is logically the same as but rather more efficient than:
+    //    SkAutoTUnref<SkPicture> pic(this->detachAsPicture(SkRect::MakeEmpty()));
+    //    pic->playback(canvas);
+    void flushAndReset(SkCanvas*);
+
 private:
     enum class State { kEmpty, kDrawPath, kDrawRect, kDrawTextBlob };
 
     State fState;
 
     template <size_t A, size_t B>
     struct Max { static const size_t val = A > B ? A : B; };
 
     static const size_t kInlineStorage = Max<sizeof(SkRecords::DrawPath),
                                          Max<sizeof(SkRecords::DrawRect),
                                              sizeof(SkRecords::DrawTextBlob)>::val>::val;
     SkAlignedSStorage<kInlineStorage> fBuffer;
 };
 
 #endif//SkMiniRecorder_DEFINED