Avoid exit due to "-e" and test failure on non-x86_64.

Review URL: http://codereview.chromium.org/164265


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@23042 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/build/install-build-deps.sh b/build/install-build-deps.sh
index 72caaed..c5f4d5f5 100755
--- a/build/install-build-deps.sh
+++ b/build/install-build-deps.sh
@@ -168,8 +168,10 @@
 # without accidentally promoting any packages from "auto" to "manual".
 # We then re-run "apt-get" with just the list of missing packages.
 echo "Finding missing packages..."
-packages="${dev_list} ${lib_list} ${dbg_list}
-                  $([ "$(uname -m)" = "x86_64" ] && echo ${cmp_list})"
+packages="${dev_list} ${lib_list} ${dbg_list}"
+if [ "$(uname -m)" = "x86_64" ]; then
+  packages+=" ${cmp_list})"
+fi
 # Intentially leaving $packages unquoted so it's more readable.
 echo "Packages required: " $packages
 echo