Switch ChromeOS Chromium login to use IJG libjpeg

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 863 matching lines @@
 
         # Enable Skia UI text drawing incrementally on different platforms.
         # http://crbug.com/105550
         #
         # On Aura, this allows per-tile painting to be used in the browser
         # compositor.
         ['OS!="android"', {
           'use_canvas_skia%': 1,
         }],
 
-        ['chromeos==1', {
-          # When building for ChromeOS we dont want Chromium to use libjpeg_turbo.
-          'use_libjpeg_turbo%': 0,
-        }],
-
         ['OS=="android"', {
           # When building as part of the Android system, use system libraries
           # where possible to reduce ROM size.
           'use_system_libjpeg%': '<(android_webview_build)',
         }],
 
         # Do not enable the Settings App on ChromeOS.
         ['enable_app_list==1 and chromeos==0', {
           'enable_settings_app%': 1,
         }, {
@@ skipping 591 matching lines @@
 
     # Chrome OS: whether to build ChromeVox from sources in the Chromium
     # repository rather than using precompiled JavaScript in
     # chrome/third_party/chromevox.  This is still experimental.
     'use_migrated_chromevox%': 1,
 
     # Chrome OS: whether to also build the upcoming version of
     # ChromeVox, which can then be enabled via a command-line switch.
     'use_chromevox_next%': 0,
 
+    # Used to set libjpeg_gyp_path. Chrome OS ui/gfx/gfx.gyp uses the IJG path
+    # for robust login screen decoding.
+    'libjpeg_ijg_gyp_path': '../third_party/libjpeg/libjpeg.gyp',
+    'libjpeg_turbo_gyp_path': '../third_party/libjpeg_turbo/libjpeg.gyp',
+
     'conditions': [
       # The version of clang shipped upstream does not find C++ headers when
       # using -stdlib=libc++ so we instead need to use the version of clang
       # coming with Xcode.
       ['OS=="ios" and use_system_libcxx==1', {
         'clang_xcode%': 1,
       }],
       # Enable the Syzygy optimization step for the official builds.
       ['OS=="win" and buildtype=="Official" and syzyasan!=1', {
         'syzygy_optimize%': 1,
@@ skipping 468 matching lines @@
       ['target_arch=="arm" or target_arch=="mipsel" or target_arch=="mips64el"', {
         'disable_glibc%': 1,
       }, {
         'disable_glibc%': 0,
       }],
 
       # Set the relative path from this file to the GYP file of the JPEG
       # library used by Chromium.
       ['use_system_libjpeg==1 or use_libjpeg_turbo==0', {
         # Configuration for using the system libjeg is here.
-        'libjpeg_gyp_path': '../third_party/libjpeg/libjpeg.gyp',
+        'libjpeg_gyp_path': '<(libjpeg_ijg_gyp_path)',
       }, {
-        'libjpeg_gyp_path': '../third_party/libjpeg_turbo/libjpeg.gyp',
+        'libjpeg_gyp_path': '<(libjpeg_turbo_gyp_path)',
       }],
 
       # Options controlling the use of GConf (the classic GNOME configuration
       # system) and GIO, which contains GSettings (the new GNOME config system).
       ['chromeos==1 or embedded==1', {
         'use_gconf%': 0,
         'use_gio%': 0,
       }, {
         'use_gconf%': 1,
         'use_gio%': 1,
@@ skipping 3771 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',
   },
 }