Fixed a bug that was introduced when we started deprecating 32bit libraries on 64bit systems.

build/install-build-deps.sh

 #!/bin/bash -e
 
 # 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.
 
 # Script to install everything needed to build chromium (well, ideally, anyway)
 # See http://code.google.com/p/chromium/wiki/LinuxBuildInstructions
 # and http://code.google.com/p/chromium/wiki/LinuxBuild64Bit
 
@@ skipping 279 matching lines @@
 
 # Install 32bit backwards compatibility support for 64bit systems
 if [ "$(uname -m)" = "x86_64" ]; then
   if test "$do_inst_lib32" != "1"
   then
     echo "NOTE: If you were expecting the option to install 32bit libs,"
     echo "please run with the --lib32 flag."
     echo
     echo "Installation complete."
     exit 0
+  else
+    # This conditional statement has been added to deprecate and eventually
+    # remove support for 32bit libraries on 64bit systems. But for the time being,

[Michael Moss, 2013/04/23 16:02:30]

nit: 80 chars here and next line.

[Markus (顧孟勤), 2013/04/23 18:05:48]

Done.

+    # we still have to support a few legacy systems (e.g. bots), where this feature
+    # is needed.
+    # We only even give the user the option to install these libraries, if they
+    # explicitly requested doing so by setting the --lib32 command line flag.
+    # And even then, we interactively ask them one more time whether they are
+    # absolutely sure.
+    # In order for that to work, we must reset the ${do_inst_lib32} variable.
+    # There are other ways to achieve the same goal. But resetting the variable
+    # is the best way to document the intended behavior -- and to allow us to
+    # gradually deprecate and then remove the obsolete code.
+    do_inst_lib32=
   fi
 
   echo "WARNING"
   echo
   echo "We no longer recommend that you use this script to install"
   echo "32bit libraries on a 64bit system. Instead, consider using the"
   echo "install-chroot.sh script to help you set up a 32bit environment"
   echo "for building and testing 32bit versions of Chrome."
   echo
   echo "The code for installing 32bit libraries on a 64bit system is"
@@ skipping 164 matching lines @@
              sed -e 's/[.]so[.][0-9].*/.so/' |
              sort -u); do
     [ "x${i##*/}" = "xld-linux.so" ] && continue
     [ -r "$i" ] && continue
     j="$(ls "$i."* | sed -e 's/.*[.]so[.]\([^.]*\)$/\1/;t;d' |
          sort -n | tail -n 1)"
     [ -r "$i.$j" ] || continue
     sudo ln -s "${i##*/}.$j" "$i"
   done
 fi