linux: use an in-tree copy of gold by default

build/common.gypi

 # Copyright (c) 2012 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.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 583 matching lines @@
 
     # Disable shadow stack keeping used by heapcheck to unwind the stacks
     # better.
     'linux_keep_shadow_stacks%': 0,
 
     # Set to 1 to link against libgnome-keyring instead of using dlopen().
     'linux_link_gnome_keyring%': 0,
     # Set to 1 to link against gsettings APIs instead of using dlopen().
     'linux_link_gsettings%': 0,
 
+    # Set to 0 to not use third_party/gold as the linker.
+    'linux_use_gold_binary%': 1,
+
     # Set Thumb compilation flags.
     'arm_thumb%': 0,
 
     # Set ARM fpu compilation flags (only meaningful if armv7==1 and
     # arm_neon==0).
     'arm_fpu%': 'vfpv3',
 
     # Enable new NPDevice API.
     'enable_new_npdevice_api%': 0,
 
@@ skipping 1379 matching lines @@
             'variables': {'linux_use_tcmalloc%': 1},
             'defines': ['USE_HEAPCHECKER'],
           }],
           ['linux_use_tcmalloc==0', {
             'defines': ['NO_TCMALLOC'],
           }],
           ['linux_keep_shadow_stacks==1', {
             'defines': ['KEEP_SHADOW_STACKS'],
             'cflags': ['-finstrument-functions'],
           }],
+          ['linux_use_gold_binary==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'ldflags': [
+                  # Put our gold binary in the search path for the linker.
+                  '-Bthird_party/gold',
+                ],
+              }],
+            ],
+          }],
         ],
       },
     }],
     # FreeBSD-specific options; note that most FreeBSD options are set above,
     # with Linux.
     ['OS=="freebsd"', {
       'target_defaults': {
         'ldflags': [
           '-Wl,--no-keep-memory',
         ],
@@ skipping 735 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }