Add variable use_concatenated_impulse_responses to control whether webaudio uses concatenated impul…

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 634 matching lines @@
         ['OS=="android" and target_arch=="arm" and android_webview_build==0', {
           # Currently only supported on Android ARM, without webview.
           # When enabled, this will also enable WebAudio on Android
           # ARM.  Default is enabled.
           'use_openmax_dl_fft%': 1,
         }, {
           'use_openmax_dl_fft%': 0,
         }],
       ],
 
+      # Set this to 1 to enable use of concatenated impulse responses
+      # for the HRTF panner in WebAudio.
+      'use_concatenated_impulse_responses': 0,
+
       # Set this to 1 to use the Google-internal file containing
       # official API keys for Google Chrome even in a developer build.
       # Setting this variable explicitly to 1 will cause your build to
       # fail if the internal file is missing.
       #
       # Set this to 0 to not use the internal file, even when it
       # exists in your checkout.
       #
       # Leave set to 2 to have this variable implicitly set to 1 if
       # you have src/google_apis/internal/google_chrome_api_keys.h in
@@ skipping 828 matching lines @@
       }],
       ['enable_app_list==1', {
         'grit_defines': ['-D', 'enable_app_list'],
       }],
       ['enable_settings_app==1', {
         'grit_defines': ['-D', 'enable_settings_app'],
       }],
       ['enable_google_now==1', {
         'grit_defines': ['-D', 'enable_google_now'],
       }],
+      ['use_concatenated_impulse_responses==1', {
+        'grit_defines': ['-D', 'use_concatenated_impulse_responses'],
+      }],
       ['clang_use_chrome_plugins==1 and OS!="win"', {
         'clang_chrome_plugins_flags': [
           '<!@(<(DEPTH)/tools/clang/scripts/plugin_flags.sh)'
         ],
       }],
 
       ['asan==1 and OS!="win"', {
         'clang%': 1,
       }],
       ['asan==1 and OS=="mac"', {
@@ skipping 2765 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',
   },
 }