remove unused xfermode methods

Bug: skia:
Change-Id: Ib0dfa7bbf3d4e73aab355df4d5f5e2a53f653809
Reviewed-on: https://skia-review.googlesource.com/19035
Reviewed-by: Mike Reed <reed@google.com>
diff --git a/src/shaders/SkComposeShader.cpp b/src/shaders/SkComposeShader.cpp
index 4455f49..135f91d 100644
--- a/src/shaders/SkComposeShader.cpp
+++ b/src/shaders/SkComposeShader.cpp
@@ -150,7 +150,7 @@
     str->append(" ShaderB: ");
     as_SB(fShaderB)->toString(str);
     if (SkBlendMode::kSrcOver != fMode) {
-        str->appendf(" Xfermode: %s", SkXfermode::ModeName(fMode));
+        str->appendf(" Xfermode: %s", SkBlendMode_Name(fMode));
     }
 
     this->INHERITED::toString(str);