Set ContentSuggestionScrollToLoad to default disabled

Once the simplified NTP is enabled for everyone, the
ContentSuggestionsScrollToLoad flag will be the only thing controlling
whether users have scroll-to-load behavior. We're not ready to roll out
scroll-to-load, so default disabling it for now.

BUG=865216

Change-Id: I55bb1fe63ee34adee2d40513c0c1c5296b3b83a7
Reviewed-on: https://chromium-review.googlesource.com/c/1259474Reviewed-by: Filip Gorski <fgorski@chromium.org>
Commit-Queue: Theresa <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#596345}

chrome/browser/android/chrome_feature_list.cc

@@ -248,7 +248,7 @@ const base::Feature kCommandLineOnNonRooted{"CommandLineOnNonRooted",
                                             base::FEATURE_DISABLED_BY_DEFAULT};
 
 const base::Feature kContentSuggestionsScrollToLoad{
-    "ContentSuggestionsScrollToLoad", base::FEATURE_ENABLED_BY_DEFAULT};
+    "ContentSuggestionsScrollToLoad", base::FEATURE_DISABLED_BY_DEFAULT};
 
 const base::Feature kContentSuggestionsThumbnailDominantColor{
     "ContentSuggestionsThumbnailDominantColor",