add missing 'extern' keyword for predictor dcl

Change-Id: Ibf3db9b6dae91e53524c31cdfccf4678b3fa1135
diff --git a/src/dsp/lossless.c b/src/dsp/lossless.c
index 1d78018..7268408 100644
--- a/src/dsp/lossless.c
+++ b/src/dsp/lossless.c
@@ -562,6 +562,10 @@
 VP8LPredictorAddSubFunc VP8LPredictorsAdd[16];
 VP8LPredictorFunc VP8LPredictors[16];
 
+// exposed plain-C implementations
+VP8LPredictorAddSubFunc VP8LPredictorsAdd_C[16];
+VP8LPredictorFunc VP8LPredictors_C[16];
+
 VP8LTransformColorInverseFunc VP8LTransformColorInverse;
 
 VP8LConvertFunc VP8LConvertBGRAToRGB;
diff --git a/src/dsp/lossless.h b/src/dsp/lossless.h
index d080fcd..280e560 100644
--- a/src/dsp/lossless.h
+++ b/src/dsp/lossless.h
@@ -34,12 +34,12 @@
 
 typedef uint32_t (*VP8LPredictorFunc)(uint32_t left, const uint32_t* const top);
 extern VP8LPredictorFunc VP8LPredictors[16];
-VP8LPredictorFunc VP8LPredictors_C[16];
+extern VP8LPredictorFunc VP8LPredictors_C[16];
 typedef void (*VP8LPredictorAddSubFunc)(const uint32_t* in,
                                         const uint32_t* upper, int num_pixels,
                                         uint32_t* out);
 extern VP8LPredictorAddSubFunc VP8LPredictorsAdd[16];
-VP8LPredictorAddSubFunc VP8LPredictorsAdd_C[16];
+extern VP8LPredictorAddSubFunc VP8LPredictorsAdd_C[16];
 
 typedef void (*VP8LProcessDecBlueAndRedFunc)(const uint32_t* src,
                                              int num_pixels, uint32_t* dst);