Fix missing data role in color management fallback

This would show as warning in gtests. Does not affect normal operation as
OpenColorIO should have a valid configuration file for Blender itself.

intern/opencolorio/fallback_impl.cc

@@ -20,11 +20,13 @@ enum TransformType {
   TRANSFORM_SRGB_TO_LINEAR,
   TRANSFORM_SCALE,
   TRANSFORM_EXPONENT,
+  TRANSFORM_NONE,
   TRANSFORM_UNKNOWN,
 };
 
 #define COLORSPACE_LINEAR ((OCIO_ConstColorSpaceRcPtr *)1)
 #define COLORSPACE_SRGB ((OCIO_ConstColorSpaceRcPtr *)2)
+#define COLORSPACE_DATA ((OCIO_ConstColorSpaceRcPtr *)3)
 
 typedef struct OCIO_PackedImageDescription {
   float *data;
@@ -165,6 +167,8 @@ OCIO_ConstColorSpaceRcPtr *FallbackImpl::configGetColorSpace(OCIO_ConstConfigRcP
     return COLORSPACE_LINEAR;
   else if (strcmp(name, "sRGB") == 0)
     return COLORSPACE_SRGB;
+  else if (strcmp(name, "data") == 0)
+    return COLORSPACE_DATA;
 
   return NULL;
 }
@@ -179,6 +183,9 @@ int FallbackImpl::configGetIndexForColorSpace(OCIO_ConstConfigRcPtr *config, con
   else if (cs == COLORSPACE_SRGB) {
     return 1;
   }
+  else if (cs == COLORSPACE_DATA) {
+    return 2;
+  }
   return -1;
 }
 
@@ -314,7 +321,10 @@ OCIO_ConstProcessorRcPtr *FallbackImpl::configGetProcessorWithNames(OCIO_ConstCo
   OCIO_ConstColorSpaceRcPtr *cs_src = configGetColorSpace(config, srcName);
   OCIO_ConstColorSpaceRcPtr *cs_dst = configGetColorSpace(config, dstName);
   FallbackTransform transform;
-  if (cs_src == COLORSPACE_LINEAR && cs_dst == COLORSPACE_SRGB) {
+  if (cs_src == COLORSPACE_DATA || cs_dst == COLORSPACE_DATA) {
+    transform.type = TRANSFORM_NONE;
+  }
+  else if (cs_src == COLORSPACE_LINEAR && cs_dst == COLORSPACE_SRGB) {
     transform.type = TRANSFORM_LINEAR_TO_SRGB;
   }
   else if (cs_src == COLORSPACE_SRGB && cs_dst == COLORSPACE_LINEAR) {
@@ -433,6 +443,9 @@ const char *FallbackImpl::colorSpaceGetName(OCIO_ConstColorSpaceRcPtr *cs)
   else if (cs == COLORSPACE_SRGB) {
     return "sRGB";
   }
+  else if (cs == COLORSPACE_DATA) {
+    return "data";
+  }
   return NULL;
 }