Remove references to an old gyp variable that's no longer supported.

content/content_shell.gypi

Index: content/content_shell.gypi
diff --git a/content/content_shell.gypi b/content/content_shell.gypi
index 21a6213b57ed2358c18ce82a6af54540d2d04032..5ff3a2ddaca21a138e9607ad24f73caa8e4778bf 100644
--- a/content/content_shell.gypi
+++ b/content/content_shell.gypi
@@ -786,21 +786,6 @@
             },
           ],
           'conditions': [
-            ['enable_webrtc==1', {
-              'variables': {
-                'libpeer_target_type%': 'static_library',
-              },
-              'conditions': [
-                ['libpeer_target_type!="static_library"', {
-                  'copies': [{
-                   'destination': '<(PRODUCT_DIR)/$(CONTENTS_FOLDER_PATH)/Libraries',
-                   'files': [
-                      '<(PRODUCT_DIR)/libpeerconnection.so',
-                    ],
-                  }],
-                }],
-              ],
-            }],
             ['icu_use_data_file_flag==1', {
               'mac_bundle_resources': [
                 '<(PRODUCT_DIR)/icudtl.dat',