Sync: add entity modification to FakeServer

This CL adds the ModifyEntity method to FakeServer. This method is used
to modify existing Sync data on the server-side in order to mimic the
commit of a different client. This CL also adds a desktop browser test,
DownloadModifiedBookmark, to make use of the feature.

Other changes in the CL:
1) Add two util methods to the Sync bookmarks test helper to count
   bookmarks by URL. This is needed because FakeServer::ModifyEntity
   does not currently handle top-level entity name changes.
2) Change the FakeServerEntity hierarchy so that its EntitySpecifics
   member is stored as a protected field in the base class. This is done
   so that the specifics can be modified as part of a FakeServer method.

BUG=365774

Review URL: https://codereview.chromium.org/1196023002

Cr-Commit-Position: refs/heads/master@{#336478}

1 files changed, 10 insertions, 3 deletions

diff --git a/sync/test/fake_server/fake_server_entity.h b/sync/test/fake_server/fake_server_entity.h
index 6c7b944..faf8347 100644
--- a/sync/test/fake_server/fake_server_entity.h
+++ b/sync/test/fake_server/fake_server_entity.h
@@ -36,6 +36,10 @@ class FakeServerEntity {
   void SetVersion(int64 version);
   const std::string& GetName() const;
 
+  // Replaces |specifics_| with |updated_specifics|. This method is meant to be
+  // used to mimic a client commit.
+  void SetSpecifics(const sync_pb::EntitySpecifics& updated_specifics);
+
   // Common data items needed by server
   virtual std::string GetParentId() const = 0;
   virtual void SerializeAsProto(sync_pb::SyncEntity* proto) = 0;
@@ -54,18 +58,21 @@ class FakeServerEntity {
 
   void SerializeBaseProtoFields(sync_pb::SyncEntity* sync_entity);
 
-  // The ModelType that categorizes this entity.
-  syncer::ModelType model_type_;
-
  private:
   // The entity's ID.
   std::string id_;
 
+  // The ModelType that categorizes this entity.
+  syncer::ModelType model_type_;
+
   // The version of this entity.
   int64 version_;
 
   // The name of the entity.
   std::string name_;
+
+  // The EntitySpecifics for the entity.
+  sync_pb::EntitySpecifics specifics_;
 };
 
 }  // namespace fake_server