codec2: change of asC2Buffer behavior

Bug: 152617675
Test: atest CtsMediaTestCases:MediaCodecBlockModelTest
Change-Id: Ie5893313840c6f1c349affca15f105520d7965cb
diff --git a/media/codec2/sfplugin/Codec2Buffer.h b/media/codec2/sfplugin/Codec2Buffer.h
index 09475ef..ff79946 100644
--- a/media/codec2/sfplugin/Codec2Buffer.h
+++ b/media/codec2/sfplugin/Codec2Buffer.h
@@ -59,6 +59,8 @@
 
     sp<ABuffer> getImageData() const { return mImageData; }
 
+    virtual void clearC2BufferRefs() {}
+
 protected:
     /**
      * canCopy() implementation for linear buffers.
@@ -102,6 +104,7 @@
             const std::shared_ptr<C2Buffer> &buffer = nullptr);
 
     std::shared_ptr<C2Buffer> asC2Buffer() override;
+    void clearC2BufferRefs() override;
     bool canCopy(const std::shared_ptr<C2Buffer> &buffer) const override;
     bool copy(const std::shared_ptr<C2Buffer> &buffer) override;
 
@@ -161,6 +164,7 @@
     virtual ~ConstLinearBlockBuffer() = default;
 
     std::shared_ptr<C2Buffer> asC2Buffer() override;
+    void clearC2BufferRefs() override;
 
 private:
     ConstLinearBlockBuffer(
@@ -280,6 +284,7 @@
     virtual ~ConstGraphicBlockBuffer() = default;
 
     std::shared_ptr<C2Buffer> asC2Buffer() override;
+    void clearC2BufferRefs() override;
     bool canCopy(const std::shared_ptr<C2Buffer> &buffer) const override;
     bool copy(const std::shared_ptr<C2Buffer> &buffer) override;