Revert "Make SPIRV optional for Metal backend"

This reverts commit 29287e1fc7.

Reason for revert:
Possible root cause of Mac failures http://crbug.com/1320588

Original change's description:
> Make SPIRV optional for Metal backend
>
> This allows clients (ie Skia) to build ANGLE without needing
> all of the additional Vulkan dependencies. Developer builds
> will continue to include both the direct and SPIRV paths, for
> debugging purposes.
>
> Bug: angleproject:7155
> Change-Id: I1c38ee19e747df8b25fd2f8e8efa3b420a4d7766
> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3605764
> Commit-Queue: Kenneth Russell <kbr@chromium.org>
> Reviewed-by: Kenneth Russell <kbr@chromium.org>
> Auto-Submit: Brian Osman <brianosman@google.com>
> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>

Bug: chromium:1320588
Change-Id: Id160118146dad1b8f1af40c60ddefd717516cd1d
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3614527
Reviewed-by: Cody Northrop <cnorthrop@google.com>
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Auto-Submit: Cody Northrop <cnorthrop@google.com>
Reviewed-by: Kenneth Russell <kbr@chromium.org>

BUILD.gn

@@ -587,8 +587,7 @@ template("translator_lib") {
     }
 
     if (!invoker.gl_d3d_only) {
-      if (angle_enable_vulkan || use_fuzzing_engine ||
-          angle_enable_msl_through_spirv) {
+      if (angle_enable_vulkan || use_fuzzing_engine || angle_enable_metal) {
         _needs_glsl_base = true
         _needs_glsl_and_vulkan_base = true
         _uses_spirv = true
@@ -603,10 +602,10 @@ template("translator_lib") {
 
       if (angle_enable_metal) {
         sources += angle_translator_lib_metal_sources
-        defines += [ "ANGLE_ENABLE_METAL" ]
-        if (angle_enable_msl_through_spirv) {
-          defines += [ "ANGLE_ENABLE_METAL_SPIRV" ]
-        }
+        defines += [
+          "ANGLE_ENABLE_METAL",
+          "ANGLE_ENABLE_METAL_SPIRV",
+        ]
       }
     }
 

gni/angle.gni

@@ -120,10 +120,6 @@ declare_args() {
   angle_has_frame_capture = angle_has_rapidjson
 }
 
-declare_args() {
-  angle_enable_msl_through_spirv = is_mac && angle_debug_layers_enabled
-}
-
 declare_args() {
   # By default, ANGLE is using a thread pool for parallel compilation.
   # Activating the delegate worker results in posting the tasks using the
@@ -147,7 +143,7 @@ declare_args() {
       ((is_win && !angle_is_winuwp) ||
        ((is_linux || is_chromeos) &&
         (angle_use_x11 || angle_use_wayland || angle_use_vulkan_display)) ||
-       is_android || is_fuchsia || is_ggp || angle_enable_msl_through_spirv)
+       is_android || is_fuchsia || is_ggp || is_mac)
 
   # When set to true, ANGLE will not use VK_KHR_surface and VK_KHR_swapchain
   # extensions. Content can be rendered only off-screen.
@@ -204,7 +200,7 @@ declare_args() {
   # the SPIR-V generation path, but leave it disabled on release.  It's still used by the metal
   # backend nevertheless.
   angle_enable_spirv_gen_through_glslang =
-      is_debug || angle_assert_always_on || angle_enable_msl_through_spirv ||
+      is_debug || angle_assert_always_on || angle_enable_metal ||
       angle_use_spirv_gen_through_glslang
 
   # ISpriteVisual windows cannot be validated and can lead to crashes if an invalid window is

src/compiler/translator/tree_ops/vulkan/EarlyFragmentTestsOptimization.h

@@ -11,7 +11,6 @@
 #define COMPILER_TRANSLATOR_TREEOPS_VULKAN_EARLYFRAGMENTTESTSOPTIMIZATION_H_
 
 #include "common/angleutils.h"
-#include "common/debug.h"
 
 namespace sh
 {

src/libANGLE/renderer/metal/BUILD.gn

@@ -65,6 +65,8 @@ _metal_backend_sources = [
   "mtl_format_utils.mm",
   "mtl_glslang_mtl_utils.h",
   "mtl_glslang_mtl_utils.mm",
+  "mtl_glslang_utils.h",
+  "mtl_glslang_utils.mm",
   "mtl_occlusion_query_pool.h",
   "mtl_occlusion_query_pool.mm",
   "mtl_render_utils.h",
@@ -82,12 +84,11 @@ _metal_backend_sources = [
   "shaders/rewrite_indices_shared.h",
 ]
 
-config("angle_metal_spirv_backend_config") {
-  defines = [ "ANGLE_ENABLE_METAL_SPIRV" ]
-}
-
 config("angle_metal_backend_config") {
-  defines = [ "ANGLE_ENABLE_METAL" ]
+  defines = [
+    "ANGLE_ENABLE_METAL",
+    "ANGLE_ENABLE_METAL_SPIRV",
+  ]
   ldflags = [
     "-weak_framework",
     "Metal",
@@ -115,14 +116,7 @@ angle_source_set("angle_metal_backend") {
     "${angle_root}:translator",
   ]
 
-  if (angle_enable_msl_through_spirv) {
-    public_configs += [ ":angle_metal_spirv_backend_config" ]
-    deps = [ "${angle_spirv_cross_dir}/gn:spirv_cross_sources" ]
-    sources += [
-      "mtl_glslang_utils.h",
-      "mtl_glslang_utils.mm",
-    ]
-  }
+  deps = [ "${angle_spirv_cross_dir}/gn:spirv_cross_sources" ]
 
   objc_flags = [
     "-Wno-nullability-completeness",