Move DstCopy on gpu into the GrXferProcessor.

BUG=skia:

Review URL: https://codereview.chromium.org/885923002
diff --git a/src/gpu/GrBatchTarget.cpp b/src/gpu/GrBatchTarget.cpp
index 6a31353..d5d8d8f 100644
--- a/src/gpu/GrBatchTarget.cpp
+++ b/src/gpu/GrBatchTarget.cpp
@@ -21,8 +21,7 @@
         BufferedFlush* bf = iter.get();
         const GrPipeline* pipeline = bf->fPipeline;
         const GrPrimitiveProcessor* primProc = bf->fPrimitiveProcessor.get();
-        fGpu->buildProgramDesc(&desc, *primProc, *pipeline, pipeline->descInfo(),
-                               bf->fBatchTracker);
+        fGpu->buildProgramDesc(&desc, *primProc, *pipeline, bf->fBatchTracker);
 
         GrGpu::DrawArgs args(primProc, pipeline, &desc, &bf->fBatchTracker);
         for (int i = 0; i < bf->fDraws.count(); i++) {
@@ -38,8 +37,7 @@
     BufferedFlush* bf = fIter.get();
     const GrPipeline* pipeline = bf->fPipeline;
     const GrPrimitiveProcessor* primProc = bf->fPrimitiveProcessor.get();
-    fGpu->buildProgramDesc(&desc, *primProc, *pipeline, pipeline->descInfo(),
-                           bf->fBatchTracker);
+    fGpu->buildProgramDesc(&desc, *primProc, *pipeline, bf->fBatchTracker);
 
     GrGpu::DrawArgs args(primProc, pipeline, &desc, &bf->fBatchTracker);
     for (int i = 0; i < bf->fDraws.count(); i++) {