Revert "[Empty States] Add empty state illustrations to tab switcher UI"

This reverts commit e108b3c.

Reason for revert: Caused issue where illustration would remain on screen on start surface. See https://crbug.com/1448283.

Original change's description:
> [Empty States] Add empty state illustrations to tab switcher UI
>
> - Add TabListEmptyCoordinator class to initialize empty state resources and use TabModelObserver and TabModelSelectorObserver to decide when to add /remove empty view.
>     Add empty state view when:
>     - a. On closing tab and normal tab count is going to be 0.
>     - b. On toggle tab model selector to normal tab model and normal tab count is 0.
>     - c On register tab switcher layout, add empty view when recycler is empty in TabListCoordinator.
>     Remove empty state view when:
>     - a. Adding a new tab.
>     - b. Undo a closed tab.
>     - c. On toggle tab model selector to go from normal tab model with 0 tab to incognito (We never apply empty view to incognito model).
>     - d. On unregister tab switcher layout.
>
> - Apply phone_tab_switcher_empty_state_illustration.xml to icon image view when form factor is phone.
> - Apply tablet_tab_switcher_empty_state_illustration.xml to icon image view when form factor is tablet.
>
> Phone demo: https://drive.google.com/file/d/17deVSRomQUQ1wj5Ml04FTM3tJ0ZXXKZo/view?usp=sharing
> Tablet demo: https://drive.google.com/file/d/1012QQcwxmBoqx7TUjOun7BlO6z2sP4o6/view?usp=sharing
>
> Change-Id: I43b89866ae612a05912b0256790cd538b38417f5
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4531843
> Reviewed-by: Theresa Sullivan <twellington@chromium.org>
> Commit-Queue: Theresa Sullivan <twellington@chromium.org>
> Code-Coverage: Findit <findit-for-me@appspot.gserviceaccount.com>
> Cr-Commit-Position: refs/heads/main@{#1147331}

(cherry picked from commit 900bddc)

Change-Id: I3e7f2bdbd89951c7e5b849fc41dd36d3b122ef30
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4557147
Commit-Queue: Neil Coronado <nemco@google.com>
Quick-Run: Neil Coronado <nemco@google.com>
Reviewed-by: Theresa Sullivan <twellington@chromium.org>
Commit-Queue: Theresa Sullivan <twellington@chromium.org>
Auto-Submit: Neil Coronado <nemco@google.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Original-Commit-Position: refs/heads/main@{#1148134}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4571340
Commit-Queue: Krishna Govind <govind@chromium.org>
Cr-Commit-Position: refs/branch-heads/5790@{#79}
Cr-Branched-From: 1d71a33-refs/heads/main@{#1148114}

chrome/android/features/start_surface/javatests/src/org/chromium/chrome/features/start_surface/InstantStartTabSwitcherTest.java

@@ -100,8 +100,7 @@
     Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE, "force-fieldtrials=Study/Group"})
 @EnableFeatures({ChromeFeatureList.TAB_GRID_LAYOUT_ANDROID,
     ChromeFeatureList.START_SURFACE_RETURN_TIME + "<Study,",
-    ChromeFeatureList.START_SURFACE_ANDROID + "<Study", ChromeFeatureList.INSTANT_START,
-    ChromeFeatureList.EMPTY_STATES})
+    ChromeFeatureList.START_SURFACE_ANDROID + "<Study", ChromeFeatureList.INSTANT_START})
 @Restriction({Restriction.RESTRICTION_TYPE_NON_LOW_END_DEVICE,
     UiRestriction.RESTRICTION_TYPE_PHONE})
 @DoNotBatch(reason = "This test suite tests startup behaviours and thus can't be batched.")

chrome/android/features/start_surface/javatests/src/org/chromium/chrome/features/start_surface/InstantStartTest.java

@@ -99,8 +99,7 @@
 @CommandLineFlags.
     Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE, "force-fieldtrials=Study/Group"})
 @EnableFeatures({ChromeFeatureList.TAB_GRID_LAYOUT_ANDROID,
-    ChromeFeatureList.START_SURFACE_ANDROID, ChromeFeatureList.INSTANT_START,
-    ChromeFeatureList.EMPTY_STATES})
+        ChromeFeatureList.START_SURFACE_ANDROID, ChromeFeatureList.INSTANT_START})
 @Restriction({Restriction.RESTRICTION_TYPE_NON_LOW_END_DEVICE,
     UiRestriction.RESTRICTION_TYPE_PHONE})
 @DoNotBatch(reason = "InstantStartTest tests startup behaviours and thus can't be batched.")

chrome/android/features/start_surface/javatests/src/org/chromium/chrome/features/start_surface/StartSurfaceBackButtonTest.java

@@ -78,8 +78,7 @@
 @UseRunnerDelegate(ChromeJUnit4RunnerDelegate.class)
 @Restriction(
         {UiRestriction.RESTRICTION_TYPE_PHONE, Restriction.RESTRICTION_TYPE_NON_LOW_END_DEVICE})
-@EnableFeatures(
-        {ChromeFeatureList.START_SURFACE_ANDROID + "<Study", ChromeFeatureList.EMPTY_STATES})
+@EnableFeatures({ChromeFeatureList.START_SURFACE_ANDROID + "<Study"})
 @DoNotBatch(reason = "StartSurface*Test tests startup behaviours and thus can't be batched.")
 @CommandLineFlags.
 Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE, "force-fieldtrials=Study/Group"})
@@ -122,6 +121,7 @@ public StartSurfaceBackButtonTest(boolean useInstantStart, boolean immediateRetu
     @Before
     public void setUp() throws IOException {
         StartSurfaceTestUtils.setUpStartSurfaceTests(mImmediateReturn, mActivityTestRule);
+
         mLayoutChangedCallbackHelper = new CallbackHelper();
 
         if (isInstantReturn()) {

chrome/android/features/start_surface/javatests/src/org/chromium/chrome/features/start_surface/StartSurfaceMVTilesTest.java

@@ -77,8 +77,7 @@
 @UseRunnerDelegate(ChromeJUnit4RunnerDelegate.class)
 @Restriction(
         {UiRestriction.RESTRICTION_TYPE_PHONE, Restriction.RESTRICTION_TYPE_NON_LOW_END_DEVICE})
-@EnableFeatures(
-        {ChromeFeatureList.START_SURFACE_ANDROID + "<Study", ChromeFeatureList.EMPTY_STATES})
+@EnableFeatures({ChromeFeatureList.START_SURFACE_ANDROID + "<Study"})
 @DoNotBatch(reason = "StartSurface*Test tests startup behaviours and thus can't be batched.")
 @CommandLineFlags.
 Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE, "force-fieldtrials=Study/Group"})

chrome/android/features/start_surface/javatests/src/org/chromium/chrome/features/start_surface/StartSurfaceTabSwitcherTest.java

@@ -78,8 +78,7 @@
 @UseRunnerDelegate(ChromeJUnit4RunnerDelegate.class)
 @Restriction(
         {UiRestriction.RESTRICTION_TYPE_PHONE, Restriction.RESTRICTION_TYPE_NON_LOW_END_DEVICE})
-@EnableFeatures(
-        {ChromeFeatureList.START_SURFACE_ANDROID + "<Study", ChromeFeatureList.EMPTY_STATES})
+@EnableFeatures({ChromeFeatureList.START_SURFACE_ANDROID + "<Study"})
 @DoNotBatch(reason = "StartSurface*Test tests startup behaviours and thus can't be batched.")
 @CommandLineFlags.
 Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE, "force-fieldtrials=Study/Group"})

chrome/android/features/start_surface/javatests/src/org/chromium/chrome/features/start_surface/StartSurfaceTest.java

@@ -116,8 +116,7 @@
 @UseRunnerDelegate(ChromeJUnit4RunnerDelegate.class)
 @Restriction(
         {UiRestriction.RESTRICTION_TYPE_PHONE, Restriction.RESTRICTION_TYPE_NON_LOW_END_DEVICE})
-@EnableFeatures(
-        {ChromeFeatureList.START_SURFACE_ANDROID + "<Study", ChromeFeatureList.EMPTY_STATES})
+@EnableFeatures({ChromeFeatureList.START_SURFACE_ANDROID + "<Study"})
 @CommandLineFlags.
 Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE, "force-fieldtrials=Study/Group"})
 @DoNotBatch(reason = "This test suite tests startup behaviors.")

chrome/android/features/tab_ui/BUILD.gn

@@ -41,7 +41,6 @@ android_resources("java_resources") {
     "java/res/drawable/ic_select_all_24dp.xml",
     "java/res/drawable/iph_drag_and_drop_animated_drawable.xml",
     "java/res/drawable/iph_drag_and_drop_drawable.xml",
-    "java/res/drawable/phone_tab_switcher_empty_state_illustration.xml",
     "java/res/drawable/price_card_background.xml",
     "java/res/drawable/price_card_scrim.xml",
     "java/res/drawable/selected_tab_background.xml",
@@ -55,7 +54,6 @@ android_resources("java_resources") {
     "java/res/drawable/tab_strip_favicon_circle.xml",
     "java/res/drawable/tab_strip_selected_ring.xml",
     "java/res/drawable/tab_strip_selected_ring_incognito.xml",
-    "java/res/drawable/tablet_tab_switcher_empty_state_illustration.xml",
     "java/res/drawable/tabstrip_favicon_background.xml",
     "java/res/drawable/ungroup_bar_background.xml",
     "java/res/layout/bottom_tab_grid_toolbar.xml",

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListCoordinator.java

@@ -30,7 +30,6 @@
 
 import org.chromium.base.Callback;
 import org.chromium.base.TraceEvent;
-import org.chromium.chrome.browser.flags.ChromeFeatureList;
 import org.chromium.chrome.browser.lifecycle.DestroyObserver;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tab.TabUtils;
@@ -82,7 +81,6 @@ public class TabListCoordinator
     static final int GRID_LAYOUT_SPAN_COUNT_LARGE = 4;
     static final int MAX_SCREEN_WIDTH_COMPACT_DP = 600;
     static final int MAX_SCREEN_WIDTH_MEDIUM_DP = 800;
-
     private final TabListMediator mMediator;
     private final TabListRecyclerView mRecyclerView;
     private final SimpleRecyclerViewAdapter mAdapter;
@@ -99,7 +97,6 @@ public class TabListCoordinator
     private @Nullable TabStripSnapshotter mTabStripSnapshotter;
     private ItemTouchHelper mItemTouchHelper;
     private OnItemTouchListener mOnItemTouchListener;
-    private TabListEmptyCoordinator mTabListEmptyCoordinator;
 
     /**
      * Construct a coordinator for UI that shows a list of tabs.
@@ -144,7 +141,6 @@ public class TabListCoordinator
         mModel = new TabListModel();
         mAdapter = new SimpleRecyclerViewAdapter(mModel);
         mRootView = rootView;
-
         RecyclerView.RecyclerListener recyclerListener = null;
         if (mMode == TabListMode.GRID || mMode == TabListMode.CAROUSEL) {
             mAdapter.registerType(UiType.SELECTABLE, parent -> {
@@ -223,10 +219,6 @@ public class TabListCoordinator
                 selectionDelegateProvider, gridCardOnClickListenerProvider, dialogHandler,
                 priceWelcomeMessageController, componentName, itemType);
 
-        if (ChromeFeatureList.sEmptyStates.isEnabled()) {
-            mTabListEmptyCoordinator = new TabListEmptyCoordinator(rootView, mModel);
-        }
-
         try (TraceEvent e = TraceEvent.scoped("TabListCoordinator.setupRecyclerView")) {
             if (!attachToParent) {
                 mRecyclerView = (TabListRecyclerView) LayoutInflater.from(context).inflate(
@@ -538,9 +530,6 @@ void postHiding() {
     @Override
     public void onDestroy() {
         mMediator.destroy();
-        if (mTabListEmptyCoordinator != null) {
-            mTabListEmptyCoordinator.destroy();
-        }
         if (mListLayoutListener != null) {
             mRecyclerView.removeOnLayoutChangeListener(mListLayoutListener);
             mLayoutListenerRegistered = false;

chrome/android/features/tab_ui/javatests/src/org/chromium/chrome/browser/tasks/tab_management/TabSwitcherAndStartSurfaceLayoutTest.java

@@ -148,7 +148,6 @@
 @CommandLineFlags.Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE,
         "force-fieldtrials=Study/Group"})
 @EnableFeatures({ChromeFeatureList.TAB_GRID_LAYOUT_ANDROID + "<Study"})
-@DisableFeatures({ChromeFeatureList.EMPTY_STATES})
 @Restriction(
         {UiRestriction.RESTRICTION_TYPE_PHONE, Restriction.RESTRICTION_TYPE_NON_LOW_END_DEVICE})
 public class TabSwitcherAndStartSurfaceLayoutTest {

chrome/android/features/tab_ui/javatests/src/org/chromium/chrome/browser/tasks/tab_management/TabSwitcherTabletTest.java

@@ -88,8 +88,8 @@
 @RunWith(ChromeJUnit4ClassRunner.class)
 @CommandLineFlags.
 Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE, "force-fieldtrials=Study/Group"})
-@EnableFeatures({ChromeFeatureList.TAB_STRIP_REDESIGN, ChromeFeatureList.EMPTY_STATES})
-@DisableFeatures({ChromeFeatureList.TAB_TO_GTS_ANIMATION})
+@EnableFeatures({ChromeFeatureList.TAB_STRIP_REDESIGN})
+@DisableFeatures(ChromeFeatureList.TAB_TO_GTS_ANIMATION)
 @Restriction(
         {Restriction.RESTRICTION_TYPE_NON_LOW_END_DEVICE, UiRestriction.RESTRICTION_TYPE_TABLET})
 @Batch(Batch.PER_CLASS)

chrome/android/features/tab_ui/tab_management_java_sources.gni

@@ -67,7 +67,6 @@ internal_tab_management_java_sources = [
   "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListContainerProperties.java",
   "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListContainerViewBinder.java",
   "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListCoordinator.java",
-  "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListEmptyCoordinator.java",
   "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListMediator.java",
   "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListModel.java",
   "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListRecyclerView.java",

chrome/android/java/src/org/chromium/chrome/browser/app/flags/ChromeCachedFlags.java

@@ -68,7 +68,6 @@ public void cacheNativeFlags() {
         CachedFeatureFlags.cacheNativeFlags(ChromeFeatureList.sFlagsCachedFullBrowser);
         CachedFeatureFlags.cacheAdditionalNativeFlags();
 
-        //clang-format off
         List<CachedFieldTrialParameter> fieldTrialsToCache = List.of(
                 BrandingController.BRANDING_CADENCE_MS,
                 BrandingController.MAX_BLANK_TOOLBAR_TIMEOUT_MS,

chrome/browser/flags/android/java/src/org/chromium/chrome/browser/flags/ChromeFeatureList.java

@@ -529,7 +529,6 @@ public static Map<String, String> getFieldTrialParamsForFeature(String featureNa
             new CachedFlag(DELAY_TEMP_STRIP_REMOVAL, true);
     public static final CachedFlag sDiscoverMultiColumn = new CachedFlag(FEED_MULTI_COLUMN, true);
     public static final CachedFlag sEarlyLibraryLoad = new CachedFlag(EARLY_LIBRARY_LOAD, true);
-    public static final CachedFlag sEmptyStates = new CachedFlag(EMPTY_STATES, true);
     public static final CachedFlag sExperimentsForAgsa = new CachedFlag(EXPERIMENTS_FOR_AGSA, true);
     public static final CachedFlag sFeedLoadingPlaceholder =
             new CachedFlag(FEED_LOADING_PLACEHOLDER, false);
@@ -628,7 +627,6 @@ public static Map<String, String> getFieldTrialParamsForFeature(String featureNa
         sDelayTempStripRemoval,
         sDiscoverMultiColumn,
         sEarlyLibraryLoad,
-        sEmptyStates,
         sFeedLoadingPlaceholder,
         sFoldableJankFix,
         sHideNonDisplayableAccountEmail,