[DO NOT MERGE] Fix the blank space on contextual card loading timeout

Root cause:
Sometimes loading contextual cards exceeds 1 second and a timeout
expires. In the past, we used the timeout in order not to update
homepage UI and to avoid screen scrolling. But we've introduced a
mechanism of card space pre-allocation to avoid flickering, so when the
timeout expires, the pre-allocated space will be always blank.

Solution:
Display a card on timeout if the one-card space is pre-allocated.

Fixes: 165886791
Test: robotest
Change-Id: I79b29c5fd6d9c4fe6b53dd4f5eab4cd3a606d76d

src/com/android/settings/homepage/contextualcards/ContextualCardManager.java

@@ -243,7 +243,7 @@ public class ContextualCardManager implements ContextualCardLoader.CardContentLo
         final MetricsFeatureProvider metricsFeatureProvider =
                 FeatureFactory.getFactory(mContext).getMetricsFeatureProvider();
 
-        //navigate back to the homepage, screen rotate or after card dismissal
+        // navigate back to the homepage, screen rotate or after card dismissal
         if (!mIsFirstLaunch) {
             onContextualCardUpdated(cardsToKeep.stream()
                     .collect(groupingBy(ContextualCard::getCardType)));
@@ -266,8 +266,17 @@ public class ContextualCardManager implements ContextualCardLoader.CardContentLo
                     SettingsEnums.ACTION_CONTEXTUAL_CARD_LOAD_TIMEOUT,
                     SettingsEnums.SETTINGS_HOMEPAGE,
                     null /* key */, (int) loadTime /* value */);
+
+            // display a card on timeout if the one-card space is pre-allocated
+            if (!cards.isEmpty() && ContextualCardLoader.getCardCount(mContext) == 1) {
+                onContextualCardUpdated(cards.stream()
+                        .collect(groupingBy(ContextualCard::getCardType)));
+                metricsFeatureProvider.action(mContext,
+                        SettingsEnums.ACTION_CONTEXTUAL_CARD_SHOW,
+                        ContextualCardLogUtils.buildCardListLog(cards));
             }
-        //only log homepage display upon a fresh launch
+        }
+        // only log homepage display upon a fresh launch
         final long totalTime = System.currentTimeMillis() - mStartTime;
         metricsFeatureProvider.action(mContext,
                 SettingsEnums.ACTION_CONTEXTUAL_HOME_SHOW, (int) totalTime);

tests/robotests/src/com/android/settings/homepage/contextualcards/ContextualCardManagerTest.java

@@ -16,6 +16,7 @@
 
 package com.android.settings.homepage.contextualcards;
 
+import static com.android.settings.homepage.contextualcards.ContextualCardLoader.CONTEXTUAL_CARD_COUNT;
 import static com.android.settings.homepage.contextualcards.ContextualCardManager.KEY_CONTEXTUAL_CARDS;
 import static com.android.settings.homepage.contextualcards.slices.SliceContextualCardRenderer.VIEW_TYPE_FULL_WIDTH;
 import static com.android.settings.homepage.contextualcards.slices.SliceContextualCardRenderer.VIEW_TYPE_HALF_WIDTH;
@@ -307,7 +308,7 @@ public class ContextualCardManagerTest {
     }
 
     @Test
-    public void onFinishCardLoading_fastLoad_shouldCallOnContextualCardUpdated() {
+    public void onFinishCardLoading_fastLoad_shouldUpdateContextualCard() {
         mManager.mStartTime = System.currentTimeMillis();
         final ContextualCardManager manager = spy(mManager);
         doNothing().when(manager).onContextualCardUpdated(anyMap());
@@ -318,7 +319,7 @@ public class ContextualCardManagerTest {
     }
 
     @Test
-    public void onFinishCardLoading_slowLoad_shouldSkipOnContextualCardUpdated() {
+    public void onFinishCardLoading_slowLoadAndNoCard_shouldNotUpdateContextualCard() {
         mManager.mStartTime = 0;
         final ContextualCardManager manager = spy(mManager);
         doNothing().when(manager).onContextualCardUpdated(anyMap());
@@ -328,6 +329,30 @@ public class ContextualCardManagerTest {
         verify(manager, never()).onContextualCardUpdated(anyMap());
     }
 
+    @Test
+    public void onFinishCardLoading_slowLoadAndNotPreAllocateSpace_shouldNotUpdateContextualCard() {
+        mManager.mStartTime = 0;
+        Settings.Global.putInt(mContext.getContentResolver(), CONTEXTUAL_CARD_COUNT, 3);
+        final ContextualCardManager manager = spy(mManager);
+        doNothing().when(manager).onContextualCardUpdated(anyMap());
+
+        manager.onFinishCardLoading(Arrays.asList(buildContextualCard(TEST_SLICE_URI)));
+
+        verify(manager, never()).onContextualCardUpdated(anyMap());
+    }
+
+    @Test
+    public void onFinishCardLoading_slowLoadAndPreAllocateSpace_shouldUpdateContextualCard() {
+        mManager.mStartTime = 0;
+        Settings.Global.putInt(mContext.getContentResolver(), CONTEXTUAL_CARD_COUNT, 1);
+        final ContextualCardManager manager = spy(mManager);
+        doNothing().when(manager).onContextualCardUpdated(anyMap());
+
+        manager.onFinishCardLoading(Arrays.asList(buildContextualCard(TEST_SLICE_URI)));
+
+        verify(manager).onContextualCardUpdated(anyMap());
+    }
+
     @Test
     public void onFinishCardLoading_newLaunch_twoLoadedCards_shouldShowTwoCards() {
         mManager.mStartTime = System.currentTimeMillis();