Make the shader token names consistent.

servers/visual/shader_language.cpp

@@ -124,6 +124,9 @@ const char *ShaderLanguage::token_names[TK_MAX] = {
 	"TYPE_ISAMPLER2D",
 	"TYPE_USAMPLER2D",
 	"TYPE_SAMPLERCUBE",
+	"INTERPOLATION_FLAT",
+	"INTERPOLATION_NO_PERSPECTIVE",
+	"INTERPOLATION_SMOOTH",
 	"PRECISION_LOW",
 	"PRECISION_MID",
 	"PRECISION_HIGH",