gdata: Trigger delta feed when search results contained unknown entries.

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

 {
    "encoding": "UTF-8",
    "feed": {
       "author": [ {
          "email": {
             "$t": "tester@testing.com"
          },
          "name": {
             "$t": "tester"
          }
@@ skipping 28 matching lines @@
          "docs$filename": {
             "$t": "SubDirectory File 1.txt"
          },
          "docs$md5Checksum": {
             "$t": "3b4382ebefec6e743578c76bbd0575ce"
          },
          "docs$size": {
             "$t": "892721"
          },
          "docs$suggestedFilename": {
-            "$t": "SubDirectory File 1.txt"
+            "$t": "SubDirectory Newly Added File.txt"
          },
          "docs$writersCanInvite": {
             "value": "true"
          },
          "gd$etag": "\"HhMOFgxXHit7ImBr\"",
          "gd$feedLink": [ {
             "href": "https://file_feed_link_url",
             "rel": "http://schemas.google.com/docs/2007/revisions"
          } ],
          "gd$lastModifiedBy": {
             "email": {
                "$t": "tester@testing.com"
             },
             "name": {
                "$t": "tester"
             }
          },
          "gd$quotaBytesUsed": {
             "$t": "892721"
          },
          "gd$resourceId": {
-            "$t": "file:subdirectory_file_1_id"
+            "$t": "file:subdirectory_newly_added_file_id"
          },
          "id": {
-            "$t": "2_file_id"
+            "$t": "newly_added_file_id"
          },
          "link": [ {
             "href": "https://file_link_alternate",
             "rel": "alternate",
             "type": "text/html"
          }, {
             "href": "https://file_link_resumable_edit_media",
             "rel": "http://schemas.google.com/g/2005#resumable-edit-media",
             "type": "application/atom+xml"
          }, {
@@ skipping 145 matching lines @@
          "$t": "2011-12-14T01:03:21.151Z"
       },
       "xmlns": "http://www.w3.org/2005/Atom",
       "xmlns$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"
 }