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

Index: chrome/test/data/chromeos/gdata/remote_file_system_apitest_root_feed.json
diff --git a/chrome/test/data/chromeos/gdata/remote_file_system_apitest_root_feed.json b/chrome/test/data/chromeos/gdata/remote_file_system_apitest_root_feed.json
index 5a7b0537b4272a8da74f1c80cabce1cc0c9ce43e..807f8fcadcb30f37146073cab08532bff44aa8ef 100644
--- a/chrome/test/data/chromeos/gdata/remote_file_system_apitest_root_feed.json
+++ b/chrome/test/data/chromeos/gdata/remote_file_system_apitest_root_feed.json
@@ -84,6 +84,10 @@
             "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": {
             "$t": "2010-11-07T05:03:54.719Z"
@@ -168,6 +172,10 @@
             "href": "https://fake_server/folder:1_folder_resource_id",
             "rel": "http://schemas.google.com/docs/2007#parent",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2010-11-07T05:03:54.719Z"
@@ -248,6 +256,10 @@
             "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": {
             "$t": "2010-11-07T05:03:54.719Z"
@@ -340,6 +352,10 @@
             "href": "https://xxx/edit/file:1_file_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2011-12-14T00:40:47.330Z"
@@ -432,6 +448,10 @@
             "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": {
             "$t": "2011-12-14T00:40:47.330Z"
@@ -524,6 +544,10 @@
             "href": "https://xxx/edit/file:3_file_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2011-12-14T00:40:47.330Z"
@@ -616,6 +640,10 @@
             "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": {
             "$t": "2011-12-14T00:40:47.330Z"
@@ -705,6 +733,10 @@
             "href": "https://xxx/edit/file:5_file_resource_id",
             "rel": "edit",
             "type": "application/atom+xml"
+         }, {
+            "href": "https://fake_server/fake_root",
+            "rel": "http://schemas.google.com/docs/2007#parent",
+            "type": "application/atom+xml"
          } ],
          "published": {
             "$t": "2011-12-14T00:40:47.330Z"