Introduce GrBatch subclasses GrDrawBatch and GrVertexBatch to prepare for non-drawing batches

src/gpu/GrPipelineBuilder.cpp

Index: src/gpu/GrPipelineBuilder.cpp
diff --git a/src/gpu/GrPipelineBuilder.cpp b/src/gpu/GrPipelineBuilder.cpp
index 1c4421836dc1cd41a8f90f062920c97de69ad58f..b0fc7b0f057fb477692f0ca87a890d6de6e62bc9 100644
--- a/src/gpu/GrPipelineBuilder.cpp
+++ b/src/gpu/GrPipelineBuilder.cpp
@@ -145,12 +145,12 @@ void GrPipelineBuilder::calcCoverageInvariantOutput(const GrPrimitiveProcessor*
     fCoverageProcInfoValid = false;
 }
 
-void GrPipelineBuilder::calcColorInvariantOutput(const GrBatch* batch) const {
+void GrPipelineBuilder::calcColorInvariantOutput(const GrDrawBatch* batch) const {
     fColorProcInfo.calcColorWithBatch(batch, fColorStages.begin(), this->numColorFragmentStages());
     fColorProcInfoValid = false;
 }
 
-void GrPipelineBuilder::calcCoverageInvariantOutput(const GrBatch* batch) const {
+void GrPipelineBuilder::calcCoverageInvariantOutput(const GrDrawBatch* batch) const {
     fCoverageProcInfo.calcCoverageWithBatch(batch, fCoverageStages.begin(),
                                             this->numCoverageFragmentStages());
     fCoverageProcInfoValid = false;