[NTP] Use lower res thumbnail images for tiles.

Confirmed with the service provider that default image size returned
is 512x512, which is fine to use as-is for tile thumbnails. Options
need to be applied to the same URL to request the image at a higher
resolution when setting as the background image. Using the high res
image for tiles causes a noticeable delay in load time.

Bug: 850314
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Ic0c758d6326ad34017831bc1340cc292242cfa79
Reviewed-on: https://chromium-review.googlesource.com/1098380
Commit-Queue: Ramya Nagarajan <ramyan@chromium.org>
Reviewed-by: Marc Treib <treib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#566992}

chrome/browser/resources/local_ntp/custom_backgrounds.js

@@ -175,7 +175,7 @@ customBackgrounds.showImageSelectionDialog = function(dialogTitle) {
   for (var i = 0; i < coll_img.length; ++i) {
     var tile = document.createElement('div');
     tile.classList.add(customBackgrounds.CLASSES.COLLECTION_TILE);
-    tile.style.backgroundImage = 'url(' + coll_img[i].imageUrl + ')';
+    tile.style.backgroundImage = 'url(' + coll_img[i].thumbnailImageUrl + ')';
     tile.id = 'img_tile_' + i;
     tile.dataset.url = coll_img[i].imageUrl;
 

chrome/browser/search/background/ntp_background_data.cc

@@ -45,8 +45,9 @@ CollectionImage& CollectionImage::operator=(CollectionImage&&) = default;
 
 bool operator==(const CollectionImage& lhs, const CollectionImage& rhs) {
   return lhs.collection_id == rhs.collection_id &&
-         lhs.asset_id == rhs.asset_id && lhs.image_url == rhs.image_url &&
-         lhs.attribution == rhs.attribution;
+         lhs.asset_id == rhs.asset_id &&
+         lhs.thumbnail_image_url == rhs.thumbnail_image_url &&
+         lhs.image_url == rhs.image_url && lhs.attribution == rhs.attribution;
 }
 
 bool operator!=(const CollectionImage& lhs, const CollectionImage& rhs) {
@@ -60,6 +61,9 @@ CollectionImage CollectionImage::CreateFromProto(
   CollectionImage collection_image;
   collection_image.collection_id = collection_id;
   collection_image.asset_id = image.asset_id();
+  // Without options added to the image, it is 512x512.
+  collection_image.thumbnail_image_url = GURL(image.image_url());
+  // TODO(ramyan): Request resolution from service, instead of setting it here.
   collection_image.image_url = GURL(
       image.image_url() + ((image.image_url().find('=') == std::string::npos)
                                ? default_image_options

chrome/browser/search/background/ntp_background_data.h

@@ -59,6 +59,8 @@ struct CollectionImage {
   std::string collection_id;
   // A unique identifier for the image.
   uint64_t asset_id;
+  // The thumbnail image URL, typically lower resolution than the image_url.
+  GURL thumbnail_image_url;
   // The image URL.
   GURL image_url;
   // The attribution list for the image.

chrome/browser/search/background/ntp_background_service_unittest.cc

@@ -169,6 +169,7 @@ TEST_F(NtpBackgroundServiceTest, GoodCollectionImagesResponse) {
   CollectionImage collection_image;
   collection_image.collection_id = "shapes";
   collection_image.asset_id = image.asset_id();
+  collection_image.thumbnail_image_url = GURL(image.image_url());
   collection_image.image_url = GURL(image.image_url() + kImageOptions);
   collection_image.attribution.push_back(image.attribution(0).text());
 
@@ -218,6 +219,7 @@ TEST_F(NtpBackgroundServiceTest, MultipleRequests) {
   CollectionImage collection_image;
   collection_image.collection_id = "shapes";
   collection_image.asset_id = image.asset_id();
+  collection_image.thumbnail_image_url = GURL(image.image_url());
   collection_image.image_url = GURL(image.image_url() + kImageOptions);
   collection_image.attribution.push_back(image.attribution(0).text());
 

chrome/browser/search/local_ntp_source.cc

@@ -263,6 +263,8 @@ base::Value ConvertCollectionImageToDict(
   images.GetList().reserve(collection_image.size());
   for (const CollectionImage& image : collection_image) {
     base::Value dict(base::Value::Type::DICTIONARY);
+    dict.SetKey("thumbnailImageUrl",
+                base::Value(image.thumbnail_image_url.spec()));
     dict.SetKey("imageUrl", base::Value(image.image_url.spec()));
     dict.SetKey("collectionId", base::Value(image.collection_id));
     base::Value attributions(base::Value::Type::LIST);