RTC_EXPORT NV12BufferInterface

Chrome and other platforms will need access to this class when sending
biplanar buffers to webrtc.

Bug: chromium:1134165
Change-Id: Ia787ab02cb9f302670d6a81e8d4963e7d8fca468
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/187181
Reviewed-by: Niels Moller <[email protected]>
Commit-Queue: Evan Shrubsole <[email protected]>
Cr-Commit-Position: refs/heads/master@{#32348}

Author: eshrubs

api/video/video_frame_buffer.h

@@ -203,7 +203,7 @@ class BiplanarYuv8Buffer : public BiplanarYuvBuffer {
 
 // Represents Type::kNV12. NV12 is full resolution Y and half-resolution
 // interleved UV.
-class NV12BufferInterface : public BiplanarYuv8Buffer {
+class RTC_EXPORT NV12BufferInterface : public BiplanarYuv8Buffer {
  public:
   Type type() const override;