Fix native crash #495

[act262]

What does this change?

When onPreviewFrame size change , old glRgbBuffer size small new size, cause yuv decode error and render texture mistake.

What is the value of this and can you measure success?

Firstly use front camera, that use small size for preview, then switch back camera, that use bigger size. if no crash so here fix.

Screenshots

[CLAassistant]

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