drive: Add showroot=true to WAPI feed URLs and ignore "no parent" entries.

chrome/test/data/chromeos/gdata/remote_file_system_apitest_root_feed.json

 {
    "encoding": "UTF-8",
    "feed": {
       "author": [ {
          "email": {
             "$t": "tester@testing.com"
          },
          "name": {
             "$t": "tester"
          }
@@ skipping 66 matching lines @@
             "rel": "self",
             "type": "application/atom+xml"
          }, {
             "href": "https://xxx/upload/folder:2_folder_resource_id",
             "rel": "http://schemas.google.com/g/2005#resumable-create-media",
             "type": "application/atom+xml"
          }, {
             "href": "https://xxx/edit/folder:1_folder_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2010-11-07T05:03:54.719Z"
          },
          "title": {
             "$t": "test_dir"
          },
          "updated": {
             "$t": "2012-01-02T00:00:00.000Z"
          }
@@ skipping 64 matching lines @@
             "rel": "edit",
             "type": "application/atom+xml"
          }, {
             "href": "https://xxx/upload/2_folder_resource_id",
             "rel": "http://schemas.google.com/g/2005#resumable-create-media",
             "type": "application/atom+xml"
          }, {
             "href": "https://fake_server/folder:1_folder_resource_id",
             "rel": "http://schemas.google.com/docs/2007#parent",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2010-11-07T05:03:54.719Z"
          },
          "title": {
             "$t": "subdir"
          },
          "updated": {
             "$t": "2011-04-01T18:34:08.234Z"
          }
@@ skipping 60 matching lines @@
             "rel": "self",
             "type": "application/atom+xml"
          }, {
             "href": "https:/xxx/edit/folder:3_folder_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
          }, {
             "href": "https://fake_server/folder:1_folder_resource_id",
             "rel": "http://schemas.google.com/docs/2007#parent",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2010-11-07T05:03:54.719Z"
          },
          "title": {
             "$t": "empty_test_dir"
          },
          "updated": {
             "$t": "2011-11-02T04:00:00.000Z"
          }
@@ skipping 72 matching lines @@
             "rel": "self",
             "type": "application/atom+xml"
          }, {
             "href": "https://fake_server/folder:1_folder_resource_id",
             "rel": "http://schemas.google.com/docs/2007#parent",
             "type": "application/atom+xml"
          }, {
             "href": "https://xxx/edit/file:1_file_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2011-12-14T00:40:47.330Z"
          },
          "title": {
             "$t": "test_file.xul"
          },
          "updated": {
             "$t": "2011-12-14T00:40:47.330Z"
          }
@@ skipping 72 matching lines @@
             "rel": "self",
             "type": "application/atom+xml"
          }, {
             "href": "https://fake_server/folder:1_folder_resource_id",
             "rel": "http://schemas.google.com/docs/2007#parent",
             "type": "application/atom+xml"
          }, {
             "href": "https://xxx/edit/file:2_file_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2011-12-14T00:40:47.330Z"
          },
          "title": {
             "$t": "test_file.tiff"
          },
          "updated": {
             "$t": "2011-04-03T11:11:10.000Z"
          }
@@ skipping 72 matching lines @@
             "rel": "self",
             "type": "application/atom+xml"
          }, {
             "href": "https://fake_server/folder:1_folder_resource_id",
             "rel": "http://schemas.google.com/docs/2007#parent",
             "type": "application/atom+xml"
          }, {
             "href": "https://xxx/edit/file:3_file_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2011-12-14T00:40:47.330Z"
          },
          "title": {
             "$t": "test_file.xul.foo"
          },
          "updated": {
             "$t": "2012-01-01T10:00:30.000Z"
          }
@@ skipping 72 matching lines @@
             "rel": "self",
             "type": "application/atom+xml"
          }, {
             "href": "https://fake_server/folder:1_folder_resource_id",
             "rel": "http://schemas.google.com/docs/2007#parent",
             "type": "application/atom+xml"
          }, {
             "href": "https://xxx/edit/file:4_file_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2011-12-14T00:40:47.330Z"
          },
          "title": {
             "$t": "test_file.tiff.foo"
          },
          "updated": {
             "$t": "2011-12-14T00:40:47.330Z"
          }
@@ skipping 69 matching lines @@
             "rel": "self",
             "type": "application/atom+xml"
          }, {
             "href": "https://fake_server/folder:1_folder_resource_id",
             "rel": "http://schemas.google.com/docs/2007#parent",
             "type": "application/atom+xml"
          }, {
             "href": "https://xxx/edit/file:5_file_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2011-12-14T00:40:47.330Z"
          },
          "title": {
             "$t": "empty_test_file.foo"
          },
          "updated": {
             "$t": "2011-12-14T00:40:47.330Z"
          }
@@ skipping 41 matching lines @@
       },
       "xmlns": "http://www.w3.org/2005/Atom",
       "xmlns$batch": "http://schemas.google.com/gdata/batch",
       "xmlns$docs": "http://schemas.google.com/docs/2007",
       "xmlns$gd": "http://schemas.google.com/g/2005",
       "xmlns$openSearch": "http://a9.com/-/spec/opensearch/1.1/"
    },
    "version": "1.0"
 }