Revert of Remove {media,p2p,pc,xmllite,xmpp}_tests.gypi files.

webrtc/libjingle/xmllite/xmllite.gyp

Index: webrtc/libjingle/xmllite/xmllite.gyp
diff --git a/webrtc/libjingle/xmllite/xmllite.gyp b/webrtc/libjingle/xmllite/xmllite.gyp
index 1d76de673c28adf9f336a492010a970644385d2c..c297b42b5ccada54ae184b37c13355d2c721467c 100644
--- a/webrtc/libjingle/xmllite/xmllite.gyp
+++ b/webrtc/libjingle/xmllite/xmllite.gyp
@@ -42,25 +42,5 @@
         'xmlprinter.h',
       ],
     },
-  ],  # targets
-  'conditions': [
-    ['include_tests==1', {
-      'targets' : [
-        {
-          'target_name': 'rtc_xmllite_unittest',
-          'type': 'none',
-          'direct_dependent_settings': {
-            'sources': [
-              'qname_unittest.cc',
-              'xmlbuilder_unittest.cc',
-              'xmlelement_unittest.cc',
-              'xmlnsstack_unittest.cc',
-              'xmlparser_unittest.cc',
-              'xmlprinter_unittest.cc',
-            ],
-          },
-        },  # target rtc_xmllite_unittest
-      ],  # targets
-    }],  # include_tests==1
-  ],  # conditions
+  ],
 }