Remove GrGLGpu mirror methods of GL draw calls

Instead make these calls directly from GrGLOpsRenderPass.

Change-Id: Id4d0812ca6b9242207e4f0c9130b43cfa375fd4f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/281637
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/GrOpsRenderPass.cpp b/src/gpu/GrOpsRenderPass.cpp
index 486a9f1..38cc0a1 100644
--- a/src/gpu/GrOpsRenderPass.cpp
+++ b/src/gpu/GrOpsRenderPass.cpp
@@ -243,6 +243,7 @@
 
 void GrOpsRenderPass::drawInstanced(int instanceCount, int baseInstance, int vertexCount,
                                     int baseVertex) {
+    SkASSERT(this->gpu()->caps()->instanceAttribSupport());
     if (!this->prepareToDraw()) {
         return;
     }
@@ -254,6 +255,7 @@
 
 void GrOpsRenderPass::drawIndexedInstanced(int indexCount, int baseIndex, int instanceCount,
                                            int baseInstance, int baseVertex) {
+    SkASSERT(this->gpu()->caps()->instanceAttribSupport());
     if (!this->prepareToDraw()) {
         return;
     }