SK_API for SkXfermode_opts_SSE2 so Chrome can initialize flattenables.

src/opts/SkXfermode_opts_SSE2.h

Index: src/opts/SkXfermode_opts_SSE2.h
diff --git a/src/opts/SkXfermode_opts_SSE2.h b/src/opts/SkXfermode_opts_SSE2.h
index f2226fa4fd446a5246312d20a158db1b7284953f..65cf873fbb5becb9a7b03430d9d26a4461fbc576 100644
--- a/src/opts/SkXfermode_opts_SSE2.h
+++ b/src/opts/SkXfermode_opts_SSE2.h
@@ -1,9 +1,10 @@
 #ifndef SkXfermode_opts_SSE2_DEFINED
 #define SkXfermode_opts_SSE2_DEFINED
 
+#include "SkTypes.h"
 #include "SkXfermode_proccoeff.h"
 
-class SkSSE2ProcCoeffXfermode : public SkProcCoeffXfermode {
+class SK_API SkSSE2ProcCoeffXfermode : public SkProcCoeffXfermode {
 public:
     SkSSE2ProcCoeffXfermode(const ProcCoeff& rec, SkXfermode::Mode mode,
                             void* procSIMD)
@@ -24,7 +25,7 @@ private:
     typedef SkProcCoeffXfermode INHERITED;
 };
 
-SkProcCoeffXfermode* SkPlatformXfermodeFactory_impl_SSE2(const ProcCoeff& rec,
-                                                         SkXfermode::Mode mode);
+SK_API SkProcCoeffXfermode* SkPlatformXfermodeFactory_impl_SSE2(const ProcCoeff& rec,
+                                                                SkXfermode::Mode mode);
 
 #endif // SkXfermode_opts_SSE2_DEFINED