Revert "Skia/Metal raster: Add viz::MetalContextProvider"

This reverts commit 45f012f3.

Reason for revert: Broke mac compile

Original change's description:
> Skia/Metal raster: Add viz::MetalContextProvider
> 
> Add viz::MetalContextProvider, and add Metal to the Skia build by
> default. Do not wire up any of this yet.
> 
> Bug: 952063
> Change-Id: I897d052bdbf046114c1ddc0527c1d3cafc8777c5
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1577296
> Reviewed-by: Brian Osman <brianosman@google.com>
> Reviewed-by: Eric Karl <ericrk@chromium.org>
> Commit-Queue: ccameron <ccameron@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#652899}

TBR=ccameron@chromium.org,brianosman@google.com,ericrk@chromium.org

Change-Id: Ic0a4f5201df55ac7ef0b8a191b572a9bbeee6dc0
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 952063
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1577783Reviewed-by: ccameron <ccameron@chromium.org>
Commit-Queue: ccameron <ccameron@chromium.org>
Cr-Commit-Position: refs/heads/master@{#652909}

components/viz/common/BUILD.gn

@@ -40,34 +40,6 @@ viz_component("resource_format_utils") {
   ]
 }
 
-if (is_mac) {
-  viz_component("metal_context_provider") {
-    output_name = "viz_metal_context_provider"
-
-    defines = [ "VIZ_METAL_CONTEXT_PROVIDER_IMPLEMENTATION" ]
-
-    sources = [
-      "gpu/metal_context_provider.h",
-      "gpu/metal_context_provider.mm",
-      "viz_metal_context_provider_export.h",
-    ]
-
-    public_deps = [
-      "//skia",
-    ]
-
-    deps = [
-      "//base",
-      "//ui/gfx",
-    ]
-
-    libs = [
-      "Metal.framework",
-      "Foundation.framework",
-    ]
-  }
-}
-
 if (enable_vulkan) {
   viz_component("vulkan_context_provider") {
     output_name = "viz_vulkan_context_provider"
@@ -284,9 +256,6 @@ viz_component("common") {
   if (enable_vulkan) {
     public_deps += [ ":vulkan_context_provider" ]
   }
-  if (is_mac) {
-    public_deps += [ ":metal_context_provider" ]
-  }
 }
 
 viz_source_set("unit_tests") {

components/viz/common/gpu/metal_context_provider.h

-// Copyright 2019 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef COMPONENTS_VIZ_COMMON_GPU_METAL_CONTEXT_PROVIDER_H_
-#define COMPONENTS_VIZ_COMMON_GPU_METAL_CONTEXT_PROVIDER_H_
-
-#include <memory>
-#include "components/viz/common/viz_metal_context_provider_export.h"
-
-class GrContext;
-
-namespace viz {
-
-// The MetalContextProvider provides a Metal-backed GrContext.
-class VIZ_METAL_CONTEXT_PROVIDER_EXPORT MetalContextProvider {
- public:
-  // Create and return a MetalContextProvider if possible. May return nullptr
-  // if no Metal devices exist.
-  static std::unique_ptr<MetalContextProvider> Create();
-  virtual ~MetalContextProvider() {}
-
-  virtual GrContext* GetGrContext() = 0;
-  virtual void* GetMTLDevice() = 0;
-};
-
-}  // namespace viz
-
-#endif  // COMPONENTS_VIZ_COMMON_GPU_METAL_CONTEXT_PROVIDER_H_

components/viz/common/gpu/metal_context_provider.mm

-// Copyright 2019 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "components/viz/common/gpu/metal_context_provider.h"
-
-#include "base/mac/scoped_nsobject.h"
-#include "third_party/skia/include/gpu/GrContext.h"
-
-#import <Metal/Metal.h>
-
-namespace viz {
-
-namespace {
-
-struct API_AVAILABLE(macos(10.11)) MetalContextProviderImpl
-    : public MetalContextProvider {
- public:
-  explicit MetalContextProviderImpl(
-      base::scoped_nsprotocol<id<MTLDevice>> device)
-      : device_(device) {
-    command_queue_.reset([device_ newCommandQueue]);
-    // GrContext::MakeMetal will take ownership of the objects passed in. Retain
-    // the objects before passing them to MakeMetal so that the objects in
-    // |this| are also valid.
-    gr_context_ =
-        GrContext::MakeMetal([device_ retain], [command_queue_ retain]);
-    DCHECK(gr_context_);
-  }
-  ~MetalContextProviderImpl() override {}
-  GrContext* GetGrContext() override { return gr_context_.get(); }
-  void* GetMTLDevice() override { return device_.get(); }
-
- private:
-  base::scoped_nsprotocol<id<MTLDevice>> device_;
-  base::scoped_nsprotocol<id<MTLCommandQueue>> command_queue_;
-  sk_sp<GrContext> gr_context_;
-};
-
-}  // namespace
-
-// static
-std::unique_ptr<MetalContextProvider> MetalContextProvider::Create() {
-  if (@available(macOS 10.11, *)) {
-    // First attempt to find a low power device to use.
-    base::scoped_nsprotocol<id<MTLDevice>> device_to_use;
-    base::scoped_nsobject<NSArray<id<MTLDevice>>> devices(MTLCopyAllDevices());
-    for (id<MTLDevice> device in devices.get()) {
-      if ([device isLowPower]) {
-        device_to_use.reset(device, base::scoped_policy::RETAIN);
-        break;
-      }
-    }
-    // Failing that, use the system default device.
-    if (!device_to_use)
-      device_to_use.reset(MTLCreateSystemDefaultDevice());
-    if (device_to_use)
-      return std::make_unique<MetalContextProviderImpl>(device_to_use);
-  }
-  // If no device was found, or if the macOS version is too old for Metal,
-  // return no context provider.
-  return nullptr;
-}
-
-}  // namespace viz

components/viz/common/viz_metal_context_provider_export.h

-// Copyright 2019 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef COMPONENTS_VIZ_COMMON_VIZ_METAL_CONTEXT_PROVIDER_EXPORT_H_
-#define COMPONENTS_VIZ_COMMON_VIZ_METAL_CONTEXT_PROVIDER_EXPORT_H_
-
-#if defined(COMPONENT_BUILD)
-#if defined(WIN32)
-
-#if defined(VIZ_METAL_CONTEXT_PROVIDER_IMPLEMENTATION)
-#define VIZ_METAL_CONTEXT_PROVIDER_EXPORT __declspec(dllexport)
-#else
-#define VIZ_METAL_CONTEXT_PROVIDER_EXPORT __declspec(dllimport)
-#endif  // defined(VIZ_METAL_CONTEXT_PROVIDER_IMPLEMENTATION)
-
-#else  // defined(WIN32)
-#if defined(VIZ_METAL_CONTEXT_PROVIDER_IMPLEMENTATION)
-#define VIZ_METAL_CONTEXT_PROVIDER_EXPORT __attribute__((visibility("default")))
-#else
-#define VIZ_METAL_CONTEXT_PROVIDER_EXPORT
-#endif
-#endif
-
-#else  // defined(COMPONENT_BUILD)
-#define VIZ_METAL_CONTEXT_PROVIDER_EXPORT
-#endif
-
-#endif  // COMPONENTS_VIZ_COMMON_VIZ_METAL_CONTEXT_PROVIDER_EXPORT_H_

skia/BUILD.gn

@@ -25,6 +25,7 @@ skia_support_skottie = true
 
 declare_args() {
   skia_whitelist_serialized_typefaces = false
+  skia_use_metal = false
 }
 
 # External-facing config for dependent code.
@@ -101,10 +102,7 @@ config("skia_config") {
   }
 
   if (is_mac) {
-    defines += [
-      "SK_BUILD_FOR_MAC",
-      "SK_METAL",
-    ]
+    defines += [ "SK_BUILD_FOR_MAC" ]
   }
 
   if (is_win) {
@@ -558,14 +556,20 @@ component("skia") {
   }
 
   if (is_mac) {
-    deps += [ ":skia_metal" ]
-    defines += [ "SK_METAL" ]
+    if (skia_use_metal) {
+      deps += [ ":skia_metal" ]
+      defines += [ "SK_METAL" ]
+      libs += [
+        "Metal.framework",
+        "Foundation.framework",
+      ]
+    }
+
     libs = [
       "AppKit.framework",
       "CoreFoundation.framework",
       "CoreGraphics.framework",
       "CoreText.framework",
-      "Metal.framework",
       "Foundation.framework",
     ]
   }
@@ -797,7 +801,7 @@ skia_source_set("skia_opts") {
 }
 
 # Split out metal sources, because they require ARC.
-if (is_mac) {
+if (is_mac && skia_use_metal) {
   skia_source_set("skia_metal") {
     defines = [ "SK_METAL" ]
     sources = skia_metal_sources