Revert 34195 - Make sure the 'use_system_*' variables are actually visible in...

build/common.gypi

Index: build/common.gypi
===================================================================
--- build/common.gypi	(revision 34212)
+++ build/common.gypi	(working copy)
@@ -44,6 +44,20 @@
           # hosts should pass an explicit target_arch to gyp.
           'target_arch%':
             '<!(uname -m | sed -e "s/i.86/ia32/;s/x86_64/x64/;s/arm.*/arm/")',
+
+          # On Linux, we use the system versions of several libraries. We end
+          # up pulling these in as .so's anyway since they are already in our
+          # transitive closure due to GTK.
+          'use_system_zlib': 1,
+          'use_system_libjpeg': 1,
+          'use_system_bzip2': 1,
+          'use_system_libpng': 1,
+          'use_system_libjpeg': 1,
+          'use_system_libxslt': 1,
+
+          # We use our own copy of libssl, although we still need to link
+          # against the rest of NSS.
+          'use_system_ssl': 0,
         }, {  # OS!="linux"
           'target_arch%': 'ia32',
         }],