Fetch images for ContentSuggestions

ios/chrome/browser/ui/content_suggestions/content_suggestions_article_item.mm

Index: ios/chrome/browser/ui/content_suggestions/content_suggestions_article_item.mm
diff --git a/ios/chrome/browser/ui/content_suggestions/content_suggestions_article_item.mm b/ios/chrome/browser/ui/content_suggestions/content_suggestions_article_item.mm
index 107f26dfed705ba66fc25064f791999c9a890bc3..dadefbb016dbdfa1751af15cc4670d860aa1a365 100644
--- a/ios/chrome/browser/ui/content_suggestions/content_suggestions_article_item.mm
+++ b/ios/chrome/browser/ui/content_suggestions/content_suggestions_article_item.mm
@@ -18,6 +18,7 @@ const CGFloat kStandardSpacing = 8;
 @interface ContentSuggestionsArticleItem ()
 
 @property(nonatomic, copy) NSString* subtitle;
+@property(nonatomic, weak) id<ContentSuggestionsArticleItemDelegate> delegate;
 
 @end
 
@@ -30,25 +31,31 @@ const CGFloat kStandardSpacing = 8;
 @synthesize image = _image;
 @synthesize articleURL = _articleURL;
 @synthesize suggestionID = _suggestionID;
+@synthesize delegate = _delegate;
+@synthesize imageBeingFetched = _imageBeingFetched;
 
 - (instancetype)initWithType:(NSInteger)type
                        title:(NSString*)title
                     subtitle:(NSString*)subtitle
-                       image:(UIImage*)image
+                    delegate:(id<ContentSuggestionsArticleItemDelegate>)delegate
                          url:(const GURL&)url {
   self = [super initWithType:type];
   if (self) {
     self.cellClass = [ContentSuggestionsArticleCell class];
     _title = [title copy];
     _subtitle = [subtitle copy];
-    _image = image;
     _articleURL = url;
+    _delegate = delegate;
   }
   return self;
 }
 
 - (void)configureCell:(ContentSuggestionsArticleCell*)cell {
   [super configureCell:cell];
+  if (!self.image && !self.imageBeingFetched) {
+    self.imageBeingFetched = YES;

[marq (ping after 24h), 2017/02/21 11:27:08]

I think it would be better to set this to YES in the delegate method for a
couple of reasons.

- It will be close to where it is set to NO, so it's easy to verify.

- If the delegate is nil, then it is never set to YES (because it isn't being
fetched).

That does mean that it's up to the delegate to maintain the state of this
variable; that should probably be documented in the header.

[gambard, 2017/02/21 15:07:53]

Done.

+    [self.delegate loadImageForArticleItem:self];
+  }
   cell.titleLabel.text = _title;
   cell.subtitleLabel.text = _subtitle;
   cell.imageView.image = _image;