Revert "[gn build] (manually) port 9b6765e784b3" anf follow-ups

9b6765e784 was reverted in 549e55b3d5.

This reverts commit 442801a7b9.
This reverts commit 929d91a556.
This reverts commit 7c2d83347f.

llvm/utils/gn/secondary/clang-tools-extra/clangd/BUILD.gn

@@ -1,4 +1,3 @@
-import("//clang-tools-extra/clangd/quality/gen_decision_forest.gni")
 import("//clang-tools-extra/clangd/xpc/enable.gni")
 import("//llvm/utils/gn/build/write_cmake_config.gni")
 
@@ -21,17 +20,10 @@ write_cmake_config("features") {
   public_configs = [ ":features_config" ]
 }
 
-gen_decision_forest("CompletionModel") {
-  model = "quality/model"
-  filename = "CompletionModel"
-  cpp_class = "clang::clangd::Example"
-}
-
 static_library("clangd") {
   output_name = "clangDaemon"
   configs += [ "//llvm/utils/gn/build:clang_code" ]
   deps = [
-    ":CompletionModel",
     ":features",
     "//clang-tools-extra/clang-tidy",
     "//clang-tools-extra/clang-tidy:all-checks",

llvm/utils/gn/secondary/clang-tools-extra/clangd/quality/gen_decision_forest.gni

@@ -1,37 +0,0 @@
-template("gen_decision_forest") {
-  model = invoker.model
-  filename = invoker.filename
-  cpp_class = invoker.cpp_class
-
-  action("${target_name}Cpp") {
-    script = "//clang-tools-extra/clangd/quality/CompletionModelCodegen.py"
-    outputs = [
-      "$target_gen_dir/$filename.cpp",
-      "$target_gen_dir/$filename.h",
-    ]
-    args = [
-      "--model",
-      rebase_path(model, root_build_dir),
-      "--output_dir",
-      rebase_path(target_gen_dir, root_build_dir),
-      "--filename",
-      filename,
-      "--cpp_class",
-      cpp_class,
-    ]
-  }
-
-  config("${target_name}Config") {
-    cflags = [ "-Wno-unused-label" ]
-  }
-
-  source_set(target_name) {
-    configs += [
-      "//llvm/utils/gn/build:clang_code",
-      ":${target_name}Config",
-    ]
-    deps = [ ":${target_name}Cpp" ]
-    include_dirs = [ "." ]
-    sources = get_target_outputs(":${target_name}Cpp")
-  }
-}

llvm/utils/gn/secondary/clang-tools-extra/clangd/unittests/BUILD.gn

@@ -1,16 +1,8 @@
-import("//clang-tools-extra/clangd/quality/gen_decision_forest.gni")
 import("//llvm/utils/unittest/unittest.gni")
 
-gen_decision_forest("DecisionForestRuntimeTest") {
-  model = "decision_forest_model"
-  filename = "DecisionForestRuntimeTest"
-  cpp_class = "::ns1::ns2::test::Example"
-}
-
 unittest("ClangdTests") {
   configs += [ "//llvm/utils/gn/build:clang_code" ]
   deps = [
-    ":DecisionForestRuntimeTest",
     "//clang-tools-extra/clang-tidy",
     "//clang-tools-extra/clangd",
     "//clang-tools-extra/clangd:features",
@@ -36,9 +28,6 @@ unittest("ClangdTests") {
 
     # To pick up the generated inc files.
     "$target_gen_dir/../../clangd/tool",
-
-    # To pick up the generated DecisionForestRuntimeTest.h file.
-    target_gen_dir,
   ]
   sources = [
     "ASTTests.cpp",
@@ -55,7 +44,6 @@ unittest("ClangdTests") {
     "ConfigCompileTests.cpp",
     "ConfigProviderTests.cpp",
     "ConfigYAMLTests.cpp",
-    "DecisionForestTests.cpp",
     "DexTests.cpp",
     "DiagnosticsTests.cpp",
     "DraftStoreTests.cpp",