[Instant Start] Disable InstantStart when AccessibilityLayout is

enabled.

Without the check, it will trigger InstantStart code path and shows
the overview list layout. A crash would happen since the overview list
layout is null.

Bug: 1110791
Change-Id: If8dfd07118effe71a001286fcf9cb0e7279c8f31
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2336306
Commit-Queue: Xi Han <hanxi@chromium.org>
Reviewed-by: Wei-Yin Chen (陳威尹) <wychen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#795445}

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

@@ -60,6 +60,7 @@ import org.chromium.chrome.browser.compositor.layouts.LayoutManagerChromeTablet;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeState;
 import org.chromium.chrome.browser.compositor.layouts.StaticLayout;
 import org.chromium.chrome.browser.compositor.layouts.content.TabContentManager;
+import org.chromium.chrome.browser.device.DeviceClassManager;
 import org.chromium.chrome.browser.flags.CachedFeatureFlags;
 import org.chromium.chrome.browser.flags.ChromeFeatureList;
 import org.chromium.chrome.browser.flags.ChromeSwitches;
@@ -79,6 +80,7 @@ import org.chromium.chrome.browser.tasks.pseudotab.TabAttributeCache;
 import org.chromium.chrome.browser.tasks.tab_management.TabUiFeatureUtilities;
 import org.chromium.chrome.browser.toolbar.top.StartSurfaceToolbarCoordinator;
 import org.chromium.chrome.browser.toolbar.top.TopToolbarCoordinator;
+import org.chromium.chrome.browser.util.ChromeAccessibilityUtil;
 import org.chromium.chrome.test.ChromeActivityTestRule;
 import org.chromium.chrome.test.ChromeJUnit4ClassRunner;
 import org.chromium.chrome.test.ChromeTabbedActivityTestRule;
@@ -786,6 +788,33 @@ public class InstantStartTest {
         Assert.assertEquals(123, ((StaticLayout) activeLayout).getCurrentTabIdForTesting());
     }
 
+    @Test
+    @SmallTest
+    @Restriction({UiRestriction.RESTRICTION_TYPE_PHONE})
+    @EnableFeatures({ChromeFeatureList.START_SURFACE_ANDROID + "<Study"})
+    @CommandLineFlags.
+    Add({ChromeSwitches.ENABLE_ACCESSIBILITY_TAB_SWITCHER, "force-fieldtrials=Study/Group",
+            IMMEDIATE_RETURN_PARAMS + "/start_surface_variation/single"})
+    public void
+    testInstantStartNotCrashWhenAccessibilityLayoutEnabled() throws IOException {
+        TestThreadUtils.runOnUiThreadBlocking(
+                () -> ChromeAccessibilityUtil.get().setAccessibilityEnabledForTesting(true));
+        Assert.assertTrue(DeviceClassManager.enableAccessibilityLayout());
+
+        createTabStateFile(new int[] {123});
+        mActivityTestRule.startMainActivityFromLauncher();
+
+        Assert.assertFalse(TabUiFeatureUtilities.supportInstantStart(false));
+        Assert.assertTrue(CachedFeatureFlags.isEnabled(ChromeFeatureList.INSTANT_START));
+        Assert.assertTrue(StartSurfaceConfiguration.isStartSurfaceEnabled());
+
+        Assert.assertEquals(1,
+                mActivityTestRule.getActivity().getTabModelSelector().getCurrentModel().getCount());
+        Layout activeLayout = mActivityTestRule.getActivity().getLayoutManager().getActiveLayout();
+        Assert.assertTrue(activeLayout instanceof StaticLayout);
+        Assert.assertEquals(123, ((StaticLayout) activeLayout).getCurrentTabIdForTesting());
+    }
+
     /**
      * Toggles the header and checks whether the header has the right status.
      *

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

@@ -167,7 +167,8 @@ public class TabUiFeatureUtilities {
     public static boolean supportInstantStart(boolean isTablet) {
         // TODO(crbug.com/1076449): Support instant start when the stack tab switcher is
         // enabled.
-        return CachedFeatureFlags.isEnabled(ChromeFeatureList.INSTANT_START) && !isTablet
+        return !DeviceClassManager.enableAccessibilityLayout()
+                && CachedFeatureFlags.isEnabled(ChromeFeatureList.INSTANT_START) && !isTablet
                 && !StartSurfaceConfiguration.isStartSurfaceStackTabSwitcherEnabled();
     }
 }