Extend PrefetchFeedFlowTest to test running in Reduced Mode.

Tests are largely the same as PrefetchFeedFlowTest with a couple of
changes in external code and in the test itself so it works in Reduced
Mode.

Bug: 959957
Change-Id: I75bdf3e149460e8734572f0b7fe6aaae61b796b3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1669656
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: Dan H <harringtond@chromium.org>
Cr-Commit-Position: refs/heads/master@{#677031}

chrome/android/javatests/src/org/chromium/chrome/browser/offlinepages/OfflineTestUtil.java

@@ -111,6 +111,20 @@ public class OfflineTestUtil {
         return result.get();
     }
 
+    public static byte[] getRawThumbnail(long offlineId)
+            throws TimeoutException, InterruptedException {
+        final AtomicReference<byte[]> result = new AtomicReference<>();
+        final CallbackHelper callbackHelper = new CallbackHelper();
+        TestThreadUtils.runOnUiThreadBlocking(() -> {
+            nativeGetRawThumbnail(offlineId, (byte[] rawThumbnail) -> {
+                result.set(rawThumbnail);
+                callbackHelper.notifyCalled();
+            });
+        });
+        callbackHelper.waitForCallback(0);
+        return result.get();
+    }
+
     // Waits for the offline model to initialize and returns an OfflinePageBridge.
     public static OfflinePageBridge getOfflinePageBridge()
             throws TimeoutException, InterruptedException {
@@ -175,6 +189,7 @@ public class OfflineTestUtil {
     private static native void nativeGetRequestsInQueue(Callback<SavePageRequest[]> callback);
     private static native void nativeGetAllPages(
             List<OfflinePageItem> offlinePages, final Callback<List<OfflinePageItem>> callback);
+    private static native void nativeGetRawThumbnail(long offlineId, Callback<byte[]> callback);
     private static native void nativeStartRequestCoordinatorProcessing();
     private static native void nativeInterceptWithOfflineError(String url, Runnable readyRunnable);
     private static native void nativeClearIntercepts();

chrome/browser/offline_pages/android/offline_test_util_jni.cc

@@ -46,7 +46,7 @@ RequestCoordinator* GetRequestCoordinator() {
   return RequestCoordinatorFactory::GetForBrowserContext(GetProfile());
 }
 OfflinePageModel* GetOfflinePageModel() {
-  return OfflinePageModelFactory::GetForBrowserContext(GetProfile());
+  return OfflinePageModelFactory::GetForKey(::android::GetLastUsedProfileKey());
 }
 
 void OnGetAllRequestsDone(
@@ -67,6 +67,15 @@ void OnGetAllPagesDone(
   base::android::RunObjectCallbackAndroid(j_callback_obj, j_result_obj);
 }
 
+void OnGetVisualsDoneExtractThumbnail(
+    const ScopedJavaGlobalRef<jobject>& j_callback_obj,
+    std::unique_ptr<OfflinePageVisuals> visuals) {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  ScopedJavaLocalRef<jbyteArray> j_bytes =
+      base::android::ToJavaByteArray(env, visuals->thumbnail);
+  base::android::RunObjectCallbackAndroid(j_callback_obj, j_bytes);
+}
+
 void OnDeletePageDone(const ScopedJavaGlobalRef<jobject>& j_callback_obj,
                       OfflinePageModel::DeletePageResult result) {
   base::android::RunIntCallbackAndroid(j_callback_obj,
@@ -191,6 +200,18 @@ void JNI_OfflineTestUtil_GetAllPages(
       &OnGetAllPagesDone, std::move(j_result_ref), std::move(j_callback_ref)));
 }
 
+void JNI_OfflineTestUtil_GetRawThumbnail(
+    JNIEnv* env,
+    jlong j_offline_id,
+    const JavaParamRef<jobject>& j_callback_obj) {
+  DCHECK(j_offline_id);
+
+  GetOfflinePageModel()->GetVisualsByOfflineId(
+      j_offline_id,
+      base::BindOnce(&OnGetVisualsDoneExtractThumbnail,
+                     ScopedJavaGlobalRef<jobject>(j_callback_obj)));
+}
+
 void JNI_OfflineTestUtil_DeletePagesByOfflineId(
     JNIEnv* env,
     const JavaParamRef<jlongArray>& j_offline_ids_array,

components/offline_pages/core/prefetch/prefetch_service_impl.cc

@@ -71,10 +71,13 @@ void PrefetchServiceImpl::ForceRefreshSuggestions() {
   if (suggestions_provider_) {
     // Feed only.
     NewSuggestionsAvailable();
-  } else {
+  } else if (suggested_articles_observer_) {
     // Zine only.
-    DCHECK(suggested_articles_observer_);
     suggested_articles_observer_->ConsumeSuggestions();
+  } else {
+    // Neither |suggestions_provider_| nor |suggested_articles_observer_| are
+    // set in reduced mode, which is only supported with Feed.
+    // ForceRefreshSuggestions() is only called in reduced mode in tests.
   }
 }