Revert[7] "replace SkXfermode obj with SkBlendMode enum in paints"

This reverts commit Ib4a154cdd5f5d1dcac921ef50d53b79a2d6a1be8.

Reason for revert: new assert from 100K bot

Original change's description:
> Revert[6] "replace SkXfermode obj with SkBlendMode enum in paints"
> 
> - perform version check in CreateProc for XfermodeImageFilter and ArithmeticImageFilter
> This reverts commit 3ed485f4249e17abb4b11f5018d03175fd1afb44.
> 
> BUG=skia:
> 
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2992
> 
> Change-Id: Ib4a154cdd5f5d1dcac921ef50d53b79a2d6a1be8
> Reviewed-on: https://skia-review.googlesource.com/2992
> Reviewed-by: Mike Reed <reed@google.com>
> Commit-Queue: Mike Reed <reed@google.com>
> 

TBR=reed@google.com,reviews@skia.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: I848e5a69c5cd67f2c14889f4f0a346652578c4ff
Reviewed-on: https://skia-review.googlesource.com/3023
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Mike Reed <reed@google.com>
diff --git a/src/utils/SkDumpCanvas.cpp b/src/utils/SkDumpCanvas.cpp
index 68bd13e..fcb24d2 100644
--- a/src/utils/SkDumpCanvas.cpp
+++ b/src/utils/SkDumpCanvas.cpp
@@ -209,8 +209,8 @@
         if (paint->getAlpha() != 0xFF) {
             str.appendf(" alpha:0x%02X", paint->getAlpha());
         }
-        if (!paint->isSrcOver()) {
-            str.appendf(" blendmode:%d", paint->getBlendMode());
+        if (paint->getXfermode()) {
+            str.appendf(" xfermode:%p", paint->getXfermode());
         }
     }
     this->dump(kSave_Verb, paint, str.c_str());
@@ -540,10 +540,8 @@
 
     if (p) {
         msg.appendf(" color:0x%08X flags:%X", p->getColor(), p->getFlags());
-        if (!p->isSrcOver()) {
-            msg.appendf(" blendmode:%d", p->getBlendMode());
-        }
         appendFlattenable(&msg, p->getShader(), "shader");
+        appendFlattenable(&msg, p->getXfermode(), "xfermode");
         appendFlattenable(&msg, p->getPathEffect(), "pathEffect");
         appendFlattenable(&msg, p->getMaskFilter(), "maskFilter");
         appendFlattenable(&msg, p->getPathEffect(), "pathEffect");