Suggestions UI - Add Data Source and Item

ios/showcase/suggestions/sc_suggestions_coordinator.mm

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "ios/showcase/suggestions/sc_suggestions_coordinator.h"
 
 #import "ios/chrome/browser/ui/suggestions/suggestions_commands.h"
+#import "ios/chrome/browser/ui/suggestions/suggestions_data_source.h"
 #import "ios/chrome/browser/ui/suggestions/suggestions_view_controller.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
-@interface SCSuggestionsCoordinator ()<SuggestionsCommands>
+@interface SCSuggestionsCoordinator ()<SuggestionsCommands> {
+  SuggestionsDataSource* _dataSource;
+}
 
 @end
 
 @implementation SCSuggestionsCoordinator
-
 @synthesize baseViewController;
 
 #pragma mark - Coordinator
 
 - (void)start {
   SuggestionsViewController* suggestion = [[SuggestionsViewController alloc]
       initWithStyle:CollectionViewControllerStyleDefault];
 
+  _dataSource = [[SuggestionsDataSource alloc] init];
+  _dataSource.collectionViewController = suggestion;

[lpromero, 2017/01/11 09:47:05]

Since you set the collectionviewcontroller here, why not removing support for
allowing a data source without collectionviewcontroller? It will simplify
greatly.

[gambard, 2017/01/11 15:10:38]

Done.

+
   suggestion.suggestionCommandHandler = self;
 
   [self.baseViewController pushViewController:suggestion animated:YES];
 }
 
 #pragma mark - SuggestionsCommands
 
 - (void)addEmptyItem {
+  [_dataSource addTextItem:@"Button clicked"
+                  subtitle:@"Item Added!"
+                 toSection:0];
 }
 
 @end