Revert "Clear and discard stencil buffers on tilers"

This reverts commit 7b2c85577d79bf1bda6b57d9af8ad793e2fc4862.

Reason for revert: nanobench hangs on chromebook bots during mipmap regeneration

Original change's description:
> Clear and discard stencil buffers on tilers
>
> Bug: skia:
> Change-Id: I42e99cb75567825ac7751fc0ec56e4c45132628b
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/210425
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Chris Dalton <csmartdalton@google.com>

TBR=egdaniel@google.com,robertphillips@google.com,csmartdalton@google.com

Change-Id: I69e04c4797b6bde934d86c83bf0348c8abadcfc3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/213824
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
diff --git a/src/gpu/GrOpList.cpp b/src/gpu/GrOpList.cpp
index 5cee97d..109289b 100644
--- a/src/gpu/GrOpList.cpp
+++ b/src/gpu/GrOpList.cpp
@@ -187,6 +187,9 @@
 }
 
 #ifdef SK_DEBUG
+static const char* op_to_name(GrLoadOp op) {
+    return GrLoadOp::kLoad == op ? "load" : GrLoadOp::kClear == op ? "clear" : "discard";
+}
 
 void GrOpList::dump(bool printDependencies) const {
     SkDebugf("--------------------------------------------------------------\n");
@@ -195,9 +198,10 @@
              fTarget.get() && fTarget.get()->peekSurface()
                      ? fTarget.get()->peekSurface()->uniqueID().asUInt()
                      : -1);
-    SkDebugf("ColorLoadOp: %s %x\n",
-             GrLoadOpName(fColorLoadOp),
-             GrLoadOp::kClear == fColorLoadOp ? fLoadClearColor.toBytes_RGBA() : 0x0);
+    SkDebugf("ColorLoadOp: %s %x StencilLoadOp: %s\n",
+             op_to_name(fColorLoadOp),
+             GrLoadOp::kClear == fColorLoadOp ? fLoadClearColor.toBytes_RGBA() : 0x0,
+             op_to_name(fStencilLoadOp));
 
     if (printDependencies) {
         SkDebugf("I rely On (%d): ", fDependencies.count());