Revert "Manage renderCmdEncoder over lifetime of GrMtlOpsRenderPass."

This reverts commit 53a72c1.

Reason for revert: Mac 10.13 bot is red

Original change's description:
> Manage renderCmdEncoder over lifetime of GrMtlOpsRenderPass.
> 
> Rather than create a renderCmdEncoder per draw, we create it up front
> and each draw just uses it. On a clear or upload we switch away and
> then recreate it.
> 
> Bug: skia:
> Change-Id: Ic6d612119ed3f7c41183d0186083deae14f96398
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/270841
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Jim Van Verth <jvanverth@google.com>

TBR=egdaniel@google.com,jvanverth@google.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: skia:
Change-Id: Ibc2697c127ec3e309ed4bb5fe84982f6047e5915
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/271496
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>

src/gpu/mtl/GrMtlCaps.mm

@@ -1057,7 +1057,7 @@ static bool format_is_srgb(MTLPixelFormat format) {
     }
 #endif
 
-    b.add32(rt->renderTargetPriv().getStencilAttachment()
+    b.add32(programInfo.pipeline().isStencilEnabled()
                                  ? this->preferredStencilFormat().fInternalFormat
                                  : MTLPixelFormatInvalid);
     b.add32((uint32_t)programInfo.pipeline().isStencilEnabled());

src/gpu/mtl/GrMtlOpsRenderPass.h

@@ -33,7 +33,10 @@ class GrMtlOpsRenderPass : public GrOpsRenderPass, private GrMesh::SendToGpuImpl
 
     void initRenderState(id<MTLRenderCommandEncoder>);
 
-    void inlineUpload(GrOpFlushState* state, GrDeferredTextureUploadFn& upload) override;
+    void inlineUpload(GrOpFlushState* state, GrDeferredTextureUploadFn& upload) override {
+        // TODO: this could be more efficient
+        state->doUpload(upload);
+    }
     void submit();
 
 private:

src/gpu/mtl/GrMtlOpsRenderPass.mm

@@ -29,11 +29,14 @@
 }
 
 GrMtlOpsRenderPass::~GrMtlOpsRenderPass() {
+    SkASSERT(nil == fActiveRenderCmdEncoder);
 }
 
 void GrMtlOpsRenderPass::precreateCmdEncoder() {
     // For clears, we may not have an associated draw. So we prepare a cmdEncoder that
     // will be submitted whether there's a draw or not.
+    SkASSERT(nil == fActiveRenderCmdEncoder);
+
     SkDEBUGCODE(id<MTLRenderCommandEncoder> cmdEncoder =)
             fGpu->commandBuffer()->getRenderCommandEncoder(fRenderPassDesc, nullptr, this);
     SkASSERT(nil != cmdEncoder);
@@ -46,7 +49,6 @@
     SkIRect iBounds;
     fBounds.roundOut(&iBounds);
     fGpu->submitIndirectCommandBuffer(fRenderTarget, fOrigin, &iBounds);
-    fActiveRenderCmdEncoder = nil;
 }
 
 GrMtlPipelineState* GrMtlOpsRenderPass::prepareDrawState(const GrProgramInfo& programInfo) {
@@ -76,10 +78,10 @@
         return;
     }
 
-    if (!fActiveRenderCmdEncoder) {
-        fActiveRenderCmdEncoder =
-                fGpu->commandBuffer()->getRenderCommandEncoder(fRenderPassDesc, nullptr, this);
-    }
+    SkASSERT(nil == fActiveRenderCmdEncoder);
+    fActiveRenderCmdEncoder = fGpu->commandBuffer()->getRenderCommandEncoder(
+            fRenderPassDesc, pipelineState, this);
+    SkASSERT(fActiveRenderCmdEncoder);
 
     [fActiveRenderCmdEncoder setRenderPipelineState:pipelineState->mtlPipelineState()];
     pipelineState->setDrawState(fActiveRenderCmdEncoder,
@@ -129,6 +131,7 @@
         mesh.sendToGpu(programInfo.primitiveType(), this);
     }
 
+    fActiveRenderCmdEncoder = nil;
     fBounds.join(bounds);
 }
 
@@ -159,16 +162,6 @@
     fRenderPassDesc.stencilAttachment.loadAction = MTLLoadActionClear;
     this->precreateCmdEncoder();
     fRenderPassDesc.stencilAttachment.loadAction = MTLLoadActionLoad;
-    fActiveRenderCmdEncoder =
-            fGpu->commandBuffer()->getRenderCommandEncoder(fRenderPassDesc, nullptr, this);
-}
-
-void GrMtlOpsRenderPass::inlineUpload(GrOpFlushState* state, GrDeferredTextureUploadFn& upload) {
-    // TODO: this could be more efficient
-    state->doUpload(upload);
-    // doUpload() creates a blitCommandEncoder, so we need to recreate a renderCommandEncoder
-    fActiveRenderCmdEncoder =
-            fGpu->commandBuffer()->getRenderCommandEncoder(fRenderPassDesc, nullptr, this);
 }
 
 void GrMtlOpsRenderPass::initRenderState(id<MTLRenderCommandEncoder> encoder) {
@@ -247,12 +240,6 @@
     } else {
         fBounds.setEmpty();
     }
-
-    // For now, we lazily create the renderCommandEncoder because we may have no draws,
-    // and an empty renderCommandEncoder can still produce output. This can cause issues
-    // when we've cleared a texture upon creation -- we'll subsequently discard the contents.
-    // This can be removed when that ordering is fixed.
-    fActiveRenderCmdEncoder = nil;
 }
 
 static MTLPrimitiveType gr_to_mtl_primitive(GrPrimitiveType primitiveType) {