Use "Organization Identifier" as prefix for gtest CFBundleIdentifier.

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")
 
 # Invokes lipo on multiple arch-specific binaries to create a fat binary.
 #
@@ skipping 277 matching lines @@
     _info_plist = _info_plist_target_output[0]
   }
 
   info_plist(target_name) {
     format = "binary1"
     extra_substitutions = []
     if (defined(invoker.extra_substitutions)) {
       extra_substitutions = invoker.extra_substitutions
     }
     extra_substitutions += [
+      "IOS_BUNDLE_ID_PREFIX=$ios_app_bundle_id_prefix",
       "IOS_DEPLOYMENT_TARGET=$ios_deployment_target",
       "IOS_PLATFORM_BUILD=$ios_platform_build",
       "IOS_PLATFORM_NAME=$ios_sdk_name",
       "IOS_PLATFORM_VERSION=$ios_sdk_version",
       "IOS_SDK_BUILD=$ios_sdk_build",
       "IOS_SDK_NAME=$ios_sdk_name$ios_sdk_version",
       "IOS_SUPPORTED_PLATFORM=$ios_sdk_platform",
     ]
     plist_templates = [
       "//build/config/ios/BuildInfo.plist",
@@ skipping 1033 matching lines @@
       "-rpath",
       "-Xlinker",
       "@loader_path/Frameworks",
     ]
   }
 }
 
 set_defaults("ios_xctest_test") {
   configs = default_executable_configs
 }