aura: Add glib dependency when appropriate.

BUG=none
TEST=browser_tests, unit_tests etc. builds

Review URL: http://codereview.chromium.org/8599003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@110762 0039d316-1c4b-4281-b951-d872f2087c98

content/content_tests.gypi

@@ -116,6 +116,11 @@
             '../build/linux/system.gyp:gtk',
           ],
         }],
+        ['use_glib == 1', {
+          'dependencies': [
+            '../build/linux/system.gyp:glib',
+          ],
+        }],
       ],
     },
     {