Correct iOS GN hermetic support.

build/config/ios/rules.gni

 # 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.
 
 import("//build/config/ios/ios_sdk.gni")
 import("//build/config/mac/base_rules.gni")
 import("//build/config/mac/symbols.gni")
+import("//build/toolchain/toolchain.gni")
 
 # Invokes lipo on multiple arch-specific binaries to create a fat binary.
 #
 # Arguments
 #
 #   arch_binary_target
 #     name of the target generating the arch-specific binaries, they must
 #     be named $target_out_dir/$toolchain_cpu/$arch_binary_output.
 #
 #   arch_binary_output
@@ skipping 50 matching lines @@
       _toolchain = _all_toolchains[_index]
       _index = _index + 1
 
       inputs +=
           [ get_label_info("$_arch_binary_target($_toolchain)",
                            "target_out_dir") + "/$_cpu/$_arch_binary_output" ]
 
       deps += [ "$_arch_binary_target($_toolchain)" ]
     }
 
-    args = [
-             "xcrun",
-             "lipo",
-             "-create",
-             "-output",
-             rebase_path("$target_out_dir/$_output_name", root_build_dir),
-           ] + rebase_path(inputs, root_build_dir)
+    args = []
+    if (!use_system_xcode) {
+      args += [
+        "--developer_dir",
+        hermetic_xcode_path,
+      ]
+    }
+    args += [
+              "xcrun",
+              "lipo",
+              "-create",
+              "-output",
+              rebase_path("$target_out_dir/$_output_name", root_build_dir),
+            ] + rebase_path(inputs, root_build_dir)
 
     if (enable_dsyms) {
       _dsyms_output_dir = "$root_out_dir/$_output_name.dSYM"
       outputs += [
         "$_dsyms_output_dir/",
         "$_dsyms_output_dir/Contents/Info.plist",
         "$_dsyms_output_dir/Contents/Resources/DWARF/$_output_name",
       ]
       args += [ "-Wcrl,dsym," + rebase_path("$root_out_dir/.", root_build_dir) ]
     }
@@ skipping 132 matching lines @@
       code_signing_outputs += [ "$_bundle_root_dir/embedded.mobileprovision" ]
     }
 
     if (defined(invoker.extra_system_frameworks)) {
       foreach(_framework, invoker.extra_system_frameworks) {
         code_signing_outputs += [ "$bundle_root_dir/Frameworks/" +
                                   get_path_info(_framework, "file") ]
       }
     }
 
-    code_signing_args = [
+    code_signing_args = []
+    if (!use_system_xcode) {
+      code_signing_args += [
+        "--developer_dir",
+        hermetic_xcode_path,
+      ]
+    }
+    code_signing_args += [
       "code-sign-bundle",
       "-t=" + ios_sdk_name,
       "-i=" + ios_code_signing_identity,
       "-e=" + rebase_path(_entitlements_path, root_build_dir),
       "-b=" + rebase_path("$target_out_dir/$_output_name", root_build_dir),
       rebase_path(bundle_root_dir, root_build_dir),
     ]
     if (!_enable_code_signing) {
       code_signing_args += [ "--disable-code-signature" ]
     }
@@ skipping 289 matching lines @@
         deps = [
           ":$_generate_info_plist",
         ]
         sources = [
           _entitlements_path,
           _info_plist_path,
         ]
         outputs = [
           _generate_entitlements_output,
         ]
-        args = [
-                 "generate-entitlements",
-                 "-e=" + rebase_path(_entitlements_path, root_build_dir),
-                 "-p=" + rebase_path(_info_plist_path, root_build_dir),
-               ] + rebase_path(outputs, root_build_dir)
+
+        args = []
+        if (!use_system_xcode) {
+          args += [
+            "--developer_dir",
+            hermetic_xcode_path,
+          ]
+        }
+        args += [
+                  "generate-entitlements",
+                  "-e=" + rebase_path(_entitlements_path, root_build_dir),
+                  "-p=" + rebase_path(_info_plist_path, root_build_dir),
+                ] + rebase_path(outputs, root_build_dir)
       }
     }
 
     _bundle_data_info_plist = target_name + "_bundle_data_info_plist"
     bundle_data(_bundle_data_info_plist) {
       forward_variables_from(invoker, [ "testonly" ])
 
       sources = get_target_outputs(":$_generate_info_plist")
       outputs = [
         "{{bundle_root_dir}}/Info.plist",
@@ skipping 780 matching lines @@
       "-rpath",
       "-Xlinker",
       "@loader_path/Frameworks",
     ]
   }
 }
 
 set_defaults("ios_xctest_test") {
   configs = default_executable_configs
 }