Move default sanitizer options into build/ so that WebRTC can import them.

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 3864 matching lines @@
                   '-Wl,--as-needed',
                 ],
                 'defines': [
                   'MEMORY_TOOL_REPLACES_ALLOCATOR',
                 ],
               }],
             ],
             # TODO(glider): enable the default options on other systems.
             'conditions': [
               ['use_sanitizer_options==1 and OS=="linux" and (chromeos==0 or target_arch!="ia32")', {
                 'dependencies': [

[kjellander_chromium, 2014/06/25 12:27:12]

I think you should do something like:
'includes': ['<(DEPTH)/build/sanitizers/sanitizers.gypi']
'dependencies': ['sanitizer_options']
instead (not sure exactly that works, but you get the idea).

-                  '<(DEPTH)/base/base.gyp:sanitizer_options',
+                  '<(DEPTH)/build/sanitizers/sanitizers.gyp:sanitizer_options',
                 ],
               }],
             ],
           }],
           ['asan==1', {
             'target_conditions': [
               ['_toolset=="target"', {
                 'cflags': [
                   '-fsanitize=address',
                   '-w',  # http://crbug.com/162783
@@ skipping 1614 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',
   },
 }