Use a sysroot for Chrome Linux official builds.

build/common.gypi

Index: build/common.gypi
===================================================================
--- build/common.gypi	(revision 198615)
+++ build/common.gypi	(working copy)
@@ -61,6 +61,9 @@
           # non-Official # builds).
           'buildtype%': 'Dev',
 
+          # Override branding to select the desired branding flavor.
+          'branding%': 'Chromium',
+
           'conditions': [
             # ChromeOS implies ash.
             ['chromeos==1', {
@@ -101,6 +104,7 @@
         'enable_hidpi%': '<(enable_hidpi)',
         'enable_touch_ui%': '<(enable_touch_ui)',
         'buildtype%': '<(buildtype)',
+        'branding%': '<(branding)',
         'host_arch%': '<(host_arch)',
 
         # Default architecture we're building for is the architecture we're
@@ -168,6 +172,14 @@
           }, {
             'use_default_render_theme%': 0,
           }],
+
+          # TODO(thestig) Remove the linux_lsb_release check after all the
+          # official Ubuntu Lucid builder are gone.
+          ['OS=="linux" and branding=="Chrome" and buildtype=="Official" and chromeos==0', {
+            'linux_lsb_release%': '<!(lsb_release -r -s)',
+          }, {
+            'linux_lsb_release%': '',
+          }], # OS=="linux" and branding=="Chrome" and buildtype=="Official" and chromeos==0
         ],
       },
 
@@ -191,11 +203,10 @@
       'enable_message_center%': '<(enable_message_center)',
       'use_default_render_theme%': '<(use_default_render_theme)',
       'buildtype%': '<(buildtype)',
+      'branding%': '<(branding)',
       'arm_version%': '<(arm_version)',
+      'linux_lsb_release%': '<(linux_lsb_release)',
 
-      # Override branding to select the desired branding flavor.
-      'branding%': 'Chromium',
-
       # Set to 1 to enable fast builds. Set to 2 for even faster builds
       # (it disables debug info for fastest compilation - only for use
       # on compile-only bots).
@@ -629,6 +640,17 @@
           'sysroot%': '<!(cd <(DEPTH) && pwd -P)/arm-sysroot',
         }], # OS=="linux" and target_arch=="arm" and chromeos==0
 
+        ['linux_lsb_release=="12.04"', {
+          'conditions': [
+            ['target_arch=="x64"', {
+              'sysroot%': '<!(cd <(DEPTH) && pwd -P)/chrome/installer/linux/internal/debian_wheezy_amd64-sysroot',
+            }],
+            ['target_arch=="ia32"', {
+              'sysroot%': '<!(cd <(DEPTH) && pwd -P)/chrome/installer/linux/internal/debian_wheezy32-sysroot',
+            }],
+        ],
+        }], # linux_lsb_release=="12.04"
+
         ['target_arch=="mipsel"', {
           'sysroot%': '<!(cd <(DEPTH) && pwd -P)/mipsel-sysroot/sysroot',
           'CXX%': '<!(cd <(DEPTH) && pwd -P)/mipsel-sysroot/bin/mipsel-linux-gnu-gcc',