Revert of Add a GN flag for the Windows multi-dll build. (patchset #3 id:40001 of https://codereview.chromium.org/1120803003/)

Reason for revert:
May have caused some link errors on windows: https://build.chromium.org/p/chromium.win/builders/Win%20x64%20GN/builds/814

Original issue's description:
> Add a GN flag for the Windows multi-dll build.
>
> The first pass of moving the other Chrome-specific build flags out of the root build config file and into the new one. This requires both ffmpeg and Blink changes to finish landing.
>
> R=scottmg@chromium.org
> TBR=ddorwin@chromium.org (widevine)
>
> Committed: https://crrev.com/edff53a35780ba2f515c7e8d4f7131c91151e1a3
> Cr-Commit-Position: refs/heads/master@{#327854}

TBR=scottmg@chromium.org,brettw@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1117063004

Cr-Commit-Position: refs/heads/master@{#327861}

31 files changed, 26 insertions, 136 deletions

diff --git a/build/config/BUILD.gn b/build/config/BUILD.gn
index 1bd666b..22cb45a 100644
--- a/build/config/BUILD.gn
+++ b/build/config/BUILD.gn
@@ -3,7 +3,6 @@
 # found in the LICENSE file.
 
 import("//build/config/allocator.gni")
-import("//build/config/chrome_build.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
diff --git a/build/config/BUILDCONFIG.gn b/build/config/BUILDCONFIG.gn
index 2274c0e..455ec0d 100644
--- a/build/config/BUILDCONFIG.gn
+++ b/build/config/BUILDCONFIG.gn
@@ -66,13 +66,11 @@ declare_args() {
   # Selects the desired build flavor. Official builds get additional
   # processing to prepare for release. Normally you will want to develop and
   # test with this flag off.
-  # TODO(brettw) move to chrome_build.gni when DEPS are updated.
   is_official_build = false
 
   # Select the desired branding flavor. False means normal Chromium branding,
   # true means official Google Chrome branding (requires extra Google-internal
   # resources).
-  # TODO(brettw) move to chrome_build.gni when DEPS are updated.
   is_chrome_branded = false
 
   # Compile for Address Sanitizer to find memory bugs.
diff --git a/build/config/chrome_build.gni b/build/config/chrome_build.gni
deleted file mode 100644
index 99e598e..0000000
--- a/build/config/chrome_build.gni
+++ /dev/null
@@ -1,21 +0,0 @@
-# Copyright 2015 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.
-
-declare_args() {
-  # Selects the desired build flavor. Official builds get additional
-  # processing to prepare for release. Normally you will want to develop and
-  # test with this flag off.
-  # TODO(brettw) move here from BUILDCONFIG.gn when DEPS are updated.
-  #is_official_build = false
-
-  # Select the desired branding flavor. False means normal Chromium branding,
-  # true means official Google Chrome branding (requires extra Google-internal
-  # resources).
-  # TODO(brettw) move here from BUILDCONFIG.gn when DEPS are updated.
-  #is_chrome_branded = false
-
-  # Break chrome.dll into multple pieces based on process type. Only available
-  # on Windows.
-  is_multi_dll_chrome = is_win && !is_component_build
-}
diff --git a/build/config/compiler/BUILD.gn b/build/config/compiler/BUILD.gn
index 95e09d9..c217154 100644
--- a/build/config/compiler/BUILD.gn
+++ b/build/config/compiler/BUILD.gn
@@ -3,7 +3,6 @@
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
-import("//build/config/chrome_build.gni")
 if (current_cpu == "arm") {
   import("//build/config/arm.gni")
 }
diff --git a/build/config/features.gni b/build/config/features.gni
index 661170e..3f63773 100644
--- a/build/config/features.gni
+++ b/build/config/features.gni
@@ -11,7 +11,6 @@
 #
 # See also build/config/ui.gni
 
-import("//build/config/chrome_build.gni")
 if (is_android) {
   import("//build/config/android/config.gni")
 }
diff --git a/build/config/mac/mac_sdk.gni b/build/config/mac/mac_sdk.gni
index 600085e..44995a3 100644
--- a/build/config/mac/mac_sdk.gni
+++ b/build/config/mac/mac_sdk.gni
@@ -2,8 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
-
 declare_args() {
   # Minimum supported version of the Mac SDK.
   mac_sdk_min = "10.6"
diff --git a/build/config/sysroot.gni b/build/config/sysroot.gni
index e5a9c2b..057971d 100644
--- a/build/config/sysroot.gni
+++ b/build/config/sysroot.gni
@@ -5,8 +5,6 @@
 # This header file defines the "sysroot" variable which is the absolute path
 # of the sysroot. If no sysroot applies, the variable will be an empty string.
 
-import("//build/config/chrome_build.gni")
-
 declare_args() {
   # The absolute path of the sysroot that is applied when compiling using
   # the target toolchain.
diff --git a/build/secondary/tools/grit/grit_rule.gni b/build/secondary/tools/grit/grit_rule.gni
index 35bbed3..09a04c1 100644
--- a/build/secondary/tools/grit/grit_rule.gni
+++ b/build/secondary/tools/grit/grit_rule.gni
@@ -75,7 +75,6 @@
 #     # You can also put deps here if the grit source depends on generated
 #     # files.
 #   }
-import("//build/config/chrome_build.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
diff --git a/chrome/BUILD.gn b/chrome/BUILD.gn
index 833dcb1..0ab9496 100644
--- a/chrome/BUILD.gn
+++ b/chrome/BUILD.gn
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//build/config/features.gni")
 import("//build/config/locales.gni")
 import("//build/config/ui.gni")
@@ -25,7 +24,7 @@ if (!is_android) {
     ]
     defines = []
     deps = []
-    data_deps = []
+    datadeps = []
 
     # TODO(GYP) mac_bundle_resources, xcode_settings
 
@@ -33,6 +32,7 @@ if (!is_android) {
 
     if (is_win) {
       sources += [
+        "$target_gen_dir/chrome_exe_version.rc",
         "//content/app/startup_helper_win.cc",
         "//content/public/common/content_switches.cc",
         "app/chrome_crash_reporter_client.cc",
@@ -145,22 +145,17 @@ if (!is_android) {
         "//third_party/adobe/flash:flapper_binaries",
         "//third_party/widevine/cdm:widevinecdmadapter",
       ]
+      # TODO(GYP) some stuff from GYP including chrome_multiple_dll.
     }
 
     if (is_linux && enable_plugins) {
       deps += [ "//pdf" ]
     }
-
-    if (is_multi_dll_chrome) {
-      defines += [ "CHROME_MULTIPLE_DLL" ]
-      data_deps += [ ":chrome_child" ]
-    }
   }
 }  # !is_android
 
 shared_library("main_dll") {
   configs += [ "//build/config/compiler:wexit_time_destructors" ]
-  defines = []
 
   deps = [
     ":browser_dependencies",
@@ -219,7 +214,8 @@ shared_library("main_dll") {
     deps += [ "//ui/compositor" ]
   }
 
-  if (is_multi_dll_chrome) {
+  #TODO(GYP) add chrome_multiple_dll support
+  if (false) {  #chrome_multiple_dll) {
     defines += [ "CHROME_MULTIPLE_DLL_BROWSER" ]
     deps += [ "//content/public/app:browser" ]
   } else {
@@ -240,55 +236,11 @@ shared_library("main_dll") {
     # TODO(GYP) Lots of other stuff in the OS=="mac" block.
   }
 
-  if (enable_plugins && !is_multi_dll_chrome) {
+  if (enable_plugins) {
     deps += [ "//pdf" ]
   }
 }
 
-if (is_multi_dll_chrome) {
-  shared_library("chrome_child") {
-    sources = [
-      "app/chrome_main.cc",
-      "app/chrome_main_delegate.cc",
-      "app/chrome_main_delegate.h",
-      "app/close_handle_hook_win.cc",
-      "app/close_handle_hook_win.h",
-    ]
-
-    configs += [ "//build/config/compiler:wexit_time_destructors" ]
-    defines = [ "CHROME_MULTIPLE_DLL_CHILD" ]
-
-    deps = [
-      ":child_dependencies",
-      ":chrome_dll_version",
-      "//chrome/browser/policy:path_parser",
-      "//content/public/app:child",
-    ]
-
-    if (is_win) {
-      deps += [ "//chrome_elf" ]
-      # TODO(GYP): PGO on Windows.
-      # ['chrome_pgo_phase==1', {
-      #   'msvs_settings': {
-      #     'VCLinkerTool': {
-      #       'LinkTimeCodeGeneration': '2',
-      #     },
-      #   },
-      # }],
-      # ['chrome_pgo_phase==2', {
-      #   'msvs_settings': {
-      #     'VCLinkerTool': {
-      #       'LinkTimeCodeGeneration': '3',
-      #     },
-      #   },
-      # }],
-    }
-    if (enable_plugins) {
-      deps += [ "//pdf" ]
-    }
-  }
-}
-
 # GYP version: chromium_browser_dependencies variable in chrome.gyp
 group("browser_dependencies") {
   deps = [
diff --git a/chrome/app/resources/BUILD.gn b/chrome/app/resources/BUILD.gn
index 97323f1..854fda7 100644
--- a/chrome/app/resources/BUILD.gn
+++ b/chrome/app/resources/BUILD.gn
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//tools/grit/grit_rule.gni")
 
 # GYP version: chrome/chrome_resources.gyp:chrome_strings
diff --git a/chrome/browser/BUILD.gn b/chrome/browser/BUILD.gn
index fc384b7..9bb4270 100644
--- a/chrome/browser/BUILD.gn
+++ b/chrome/browser/BUILD.gn
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
diff --git a/chrome/browser/policy/BUILD.gn b/chrome/browser/policy/BUILD.gn
index e3b8e91..6a645e7 100644
--- a/chrome/browser/policy/BUILD.gn
+++ b/chrome/browser/policy/BUILD.gn
@@ -2,7 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-source_set("path_parser") {
+static_library("path_parser") {
   sources = [
     "policy_path_parser.h",
     "policy_path_parser_linux.cc",
diff --git a/chrome/chrome_dll.gypi b/chrome/chrome_dll.gypi
index 94a61a6..b9a9973 100644
--- a/chrome/chrome_dll.gypi
+++ b/chrome/chrome_dll.gypi
@@ -326,7 +326,6 @@
     ['chrome_multiple_dll', {
       'targets': [
         {
-          # GN version: //chrome:chrome_child
           'target_name': 'chrome_child_dll',
           'type': 'shared_library',
           'product_name': 'chrome_child',
diff --git a/chrome/chrome_repack_locales.gni b/chrome/chrome_repack_locales.gni
index d19888c..ea9b432 100644
--- a/chrome/chrome_repack_locales.gni
+++ b/chrome/chrome_repack_locales.gni
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//tools/grit/repack.gni")
diff --git a/chrome/common/BUILD.gn b/chrome/common/BUILD.gn
index 1985599..7de5abb 100644
--- a/chrome/common/BUILD.gn
+++ b/chrome/common/BUILD.gn
@@ -277,6 +277,7 @@ static_library("constants") {
     "widevine_cdm_constants.cc",
     "widevine_cdm_constants.h",
   ]
+  sources += get_target_outputs(":make_chrome_version")
 
   deps = [
     ":make_chrome_version",
diff --git a/chrome/installer/util/BUILD.gn b/chrome/installer/util/BUILD.gn
index f9744cb..8dca7ce 100644
--- a/chrome/installer/util/BUILD.gn
+++ b/chrome/installer/util/BUILD.gn
@@ -2,8 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
-
 static_library("util") {
   deps = [
     "//base",
diff --git a/chrome/policy.gypi b/chrome/policy.gypi
index 6d81c9c..79cc543 100644
--- a/chrome/policy.gypi
+++ b/chrome/policy.gypi
@@ -5,7 +5,6 @@
 {
   'targets': [
     {
-      # GN version: //chrome/browser/policy:path_parser
       'target_name': 'policy_path_parser',
       'type': 'static_library',
       'dependencies': [
diff --git a/chrome/test/BUILD.gn b/chrome/test/BUILD.gn
index c297978..8268f25 100644
--- a/chrome/test/BUILD.gn
+++ b/chrome/test/BUILD.gn
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
diff --git a/chrome/version.gni b/chrome/version.gni
index 1d424a6..b956e9c 100644
--- a/chrome/version.gni
+++ b/chrome/version.gni
@@ -2,15 +2,10 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
-
 # Runs the version processing script over the given template file to produce
 # an output file. This is used for generating various forms of files that
 # incorporate the product name and version.
 #
-# Unlike GYP, this will actually compile the resulting file, so you don't need
-# to add it separately to the sources, just depend on the target.
-#
 # This template automatically includes VERSION, LASTCHANGE, and BRANDING. It
 # automatically uses the template file .
 # GYP parameterizes this template file but all current invocations use this
@@ -55,11 +50,10 @@ template("process_version") {
          "Either sources or template_file must be defined for $target_name")
   assert(defined(invoker.output), "Output must be defined for $target_name")
 
-  action_name = target_name + "_action"
-  source_set_name = target_name
-
-  action(action_name) {
-    visibility = [ ":$source_set_name" ]
+  action(target_name) {
+    if (defined(invoker.visibility)) {
+      visibility = invoker.visibility
+    }
     script = "//build/util/version.py"
 
     lastchange_path = "//build/util/LASTCHANGE"
@@ -114,14 +108,4 @@ template("process_version") {
       rebase_path(invoker.output, root_build_dir),
     ]
   }
-
-  source_set(source_set_name) {
-    if (defined(invoker.visibility)) {
-      visibility = invoker.visibility
-    }
-    sources = get_target_outputs(":$action_name")
-    deps = [
-      ":$action_name",
-    ]
-  }
 }
diff --git a/chrome_elf/BUILD.gn b/chrome_elf/BUILD.gn
index ee00fa8..06cb937 100644
--- a/chrome_elf/BUILD.gn
+++ b/chrome_elf/BUILD.gn
@@ -14,6 +14,7 @@ process_version("chrome_elf_resources") {
 
 shared_library("chrome_elf") {
   sources = [
+    "$target_gen_dir/chrome_elf_version.rc",
     "chrome_elf_main.cc",
     "chrome_elf_main.h",
   ]
diff --git a/components/policy/BUILD.gn b/components/policy/BUILD.gn
index f80c492..b373cc3 100644
--- a/components/policy/BUILD.gn
+++ b/components/policy/BUILD.gn
@@ -2,9 +2,8 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//build/config/features.gni")
-import("//components/policy/resources/policy_templates.gni")
+import("resources/policy_templates.gni")
 import("//third_party/protobuf/proto_library.gni")
 import("//tools/grit/grit_rule.gni")
 
diff --git a/content/app/BUILD.gn b/content/app/BUILD.gn
index 8da75d4..f6c72b9 100644
--- a/content/app/BUILD.gn
+++ b/content/app/BUILD.gn
@@ -2,7 +2,8 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
+# TODO(GYP) enable chrome_multiple_dll support
+is_chrome_multiple_dll = false
 
 content_app_sources = [
   "android/app_jni_registrar.cc",
@@ -70,7 +71,7 @@ content_app_extra_configs = [
   "//content:content_implementation",
 ]
 
-if (!is_multi_dll_chrome) {
+if (!is_chrome_multiple_dll) {
   content_app_deps += [ "//content/gpu:gpu_sources" ]
 }
 
@@ -85,7 +86,7 @@ source_set("both") {
   deps = content_app_deps
 }
 
-if (is_multi_dll_chrome) {
+if (is_chrome_multiple_dll) {
   # It doesn't make sense to do the browser/child dll split in component mode.
   assert(!is_component_build)
 
@@ -96,7 +97,7 @@ if (is_multi_dll_chrome) {
     configs += content_app_extra_configs
     deps = content_app_deps
 
-    defines = [ "CHROME_MULTIPLE_DLL_BROWSER" ]
+    defines += [ "CHROME_MULTIPLE_DLL_BROWSER" ]
   }
 
   source_set("child") {
@@ -106,6 +107,6 @@ if (is_multi_dll_chrome) {
     configs += content_app_extra_configs
     deps = content_app_deps
 
-    defines = [ "CHROME_MULTIPLE_DLL_CHILD" ]
+    defines += [ "CHROME_MULTIPLE_DLL_CHILD" ]
   }
 }
diff --git a/content/public/app/BUILD.gn b/content/public/app/BUILD.gn
index d75b59e..20ee710 100644
--- a/content/public/app/BUILD.gn
+++ b/content/public/app/BUILD.gn
@@ -20,8 +20,6 @@
 #     //content (shared library) ->
 #       //content/public/app:both_sources (source set)
 
-import("//build/config/chrome_build.gni")
-
 public_app_shared_sources = [
   "content_jni_onload.h",
   "content_main.h",
@@ -93,7 +91,10 @@ if (is_component_build) {
            ]
   }
 
-  if (is_multi_dll_chrome) {
+  # TODO(GYP) enable chrome_multiple_dll support
+  is_chrome_multiple_dll = false
+
+  if (is_chrome_multiple_dll) {
     source_set("browser") {
       check_includes = false  # See comment above.
 
diff --git a/content/test/BUILD.gn b/content/test/BUILD.gn
index 0d0893a..8a535d8 100644
--- a/content/test/BUILD.gn
+++ b/content/test/BUILD.gn
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
diff --git a/gpu/config/BUILD.gn b/gpu/config/BUILD.gn
index 1300cca..0a2c135 100644
--- a/gpu/config/BUILD.gn
+++ b/gpu/config/BUILD.gn
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//build/config/ui.gni")
 
 declare_args() {
diff --git a/remoting/remoting_version.gni b/remoting/remoting_version.gni
index cb8fb659..f8f6276 100644
--- a/remoting/remoting_version.gni
+++ b/remoting/remoting_version.gni
@@ -2,8 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
-
 _version_py_abspath = "//build/util/version.py"
 _remoting_version_abspath = "//remoting/VERSION"
 _chrome_version_abspath = "//chrome/VERSION"
diff --git a/remoting/webapp/build_template.gni b/remoting/webapp/build_template.gni
index 5d4233c..70ff555 100644
--- a/remoting/webapp/build_template.gni
+++ b/remoting/webapp/build_template.gni
@@ -4,7 +4,6 @@
 
 # Keep in sync with 'remoting_webapp' target in remoting/remoting_client.gypi.
 
-import("//build/config/chrome_build.gni")
 import("//remoting/remoting_locales.gni")
 import("//remoting/remoting_options.gni")
 import("//remoting/remoting_version.gni")
diff --git a/third_party/adobe/flash/BUILD.gn b/third_party/adobe/flash/BUILD.gn
index 6a15c0b..7a5c99a 100644
--- a/third_party/adobe/flash/BUILD.gn
+++ b/third_party/adobe/flash/BUILD.gn
@@ -2,8 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
-
 if (is_chrome_branded) {
   if (is_linux && current_cpu == "x86") {
     flapper_version_h_file = "symbols/ppapi/linux/flapper_version.h"
diff --git a/third_party/harfbuzz-ng/BUILD.gn b/third_party/harfbuzz-ng/BUILD.gn
index ac22155..b370348 100644
--- a/third_party/harfbuzz-ng/BUILD.gn
+++ b/third_party/harfbuzz-ng/BUILD.gn
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//build/config/linux/pkg_config.gni")
 
 # The GYP build supports system harfbuzz for non-official builds when using
diff --git a/third_party/widevine/cdm/BUILD.gn b/third_party/widevine/cdm/BUILD.gn
index 62dad95..10a61b9 100644
--- a/third_party/widevine/cdm/BUILD.gn
+++ b/third_party/widevine/cdm/BUILD.gn
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chrome_build.gni")
 import("//build/config/features.gni")
 import("//chrome/version.gni")  # TODO layering violation
 import("//media/cdm/ppapi/cdm_adapter.gni")
diff --git a/tools/gn/docs/cookbook.md b/tools/gn/docs/cookbook.md
index 57df03c..2337b83 100644
--- a/tools/gn/docs/cookbook.md
+++ b/tools/gn/docs/cookbook.md
@@ -167,11 +167,10 @@ places are noted in the table below.
 | `arm_neon_optional` (0/1)                       | `arm_optionally_use_neon` (true/false)     | `//build/config/arm.gni`                       |
 | `arm_version`                                   | `arm_version`                              | `//build/config/arm.gni`                       |
 | `asan` (0/1)                                    | `is_asan` (true/false)                     | (global)                                       |
-| `branding` ("Chromium"/"Chrome"")               | `is_chrome_branded` (true/false)           | `//build/config/chrome_build.gni`              |
+| `branding` ("Chromium"/"Chrome"")               | `is_chrome_branded` (true/false)           | (global)                                       |
 | `build_for_tool=="drmemory"`                    | `disable_iterator_debugging` (true/false)  | (internal to `//build/config/BUILD.gn`)        |
 | `build_for_tool=="tsan"`                        | `disable_iterator_debugging` (true/false)  | (internal to `//build/config/BUILD.gn`)        |
-| `buildtype` ("Official"/"Dev")                  | `is_official_build` (true/false)           | `//build/config/chrome_build.gni`              |
-| `chrome_multiple_dll` (0/1)                     | `is_multi_dll_chrome` (true/false)         | `//build/config/chrome_build.gni`              |
+| `buildtype` ("Official"/"Dev")                  | `is_official_build` (true/false)           | (global)                                       |
 | `clang` (0/1)                                   | `is_clang` (true/false)                    | (global)                                       |
 | `clang_use_chrome_plugins` (0/1)                | `clang_use_chrome_plugins` (true/false)    | (internal to `//build/config/clang/BUILD.gn`)  |
 | `component` ("shared_library"/"static_library") | `is_component_build` (true/false)          | (global)                                       |