Delete GetExecutablePath and related unused code.

webrtc/base/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/crypto.gni")
 import("//build/config/ui.gni")
@@ skipping 652 matching lines @@
       "unittest_main.cc",
     ]
     configs += [ "..:common_config" ]
     public_configs = [
       "..:common_inherited_config",
       ":rtc_base_tests_utils_exported_config",
     ]
     deps = [
       ":rtc_base",
       "../test:field_trial",
+      "../test:test_support",
     ]
     public_deps = [
       "//testing/gtest",
     ]
   }
 }