[Android][WebSignin] Enable back-pressing on incognito interstitial

This CL enables back-pressing on incognito interstitial in web sign-in
bottom sheet to return to the expanded account list.

Bug: 1122007
Change-Id: I916e30f4a48db28316ecba37480a6d2fb4be5e01
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2392456Reviewed-by: Tanmoy Mollik <triploblastic@chromium.org>
Commit-Queue: Alice Wang <aliceywang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#804726}

chrome/android/java/src/org/chromium/chrome/browser/signin/account_picker/AccountPickerBottomSheetMediator.java

@@ -102,8 +102,13 @@ class AccountPickerBottomSheetMediator implements AccountPickerCoordinator.Liste
             mModel.set(AccountPickerBottomSheetProperties.VIEW_STATE,
                     ViewState.COLLAPSED_ACCOUNT_LIST);
             return true;
+        } else if (viewState == ViewState.INCOGNITO_INTERSTITIAL) {
+            mModel.set(
+                    AccountPickerBottomSheetProperties.VIEW_STATE, ViewState.EXPANDED_ACCOUNT_LIST);
+            return true;
+        } else {
+            return false;
         }
-        return false;
     }
 
     PropertyModel getModel() {

chrome/android/java/src/org/chromium/chrome/browser/signin/account_picker/AccountPickerBottomSheetView.java

@@ -116,10 +116,16 @@ class AccountPickerBottomSheetView implements BottomSheetContent {
      * Expands the account list.
      */
     void expandAccountList() {
+        mLogoImage.setImageResource(R.drawable.chrome_sync_logo);
+        mAccountPickerTitle.setText(R.string.signin_account_picker_dialog_title);
+        mAccountPickerSubtitle.setText(R.string.signin_account_picker_bottom_sheet_subtitle);
+        mAccountPickerSubtitle.setVisibility(View.VISIBLE);
+        mHorizontalDivider.setVisibility(View.VISIBLE);
         mAccountListView.setVisibility(View.VISIBLE);
 
         mSelectedAccountView.setVisibility(View.GONE);
         mContinueAsButton.setVisibility(View.GONE);
+        mIncognitoInterstitialView.setVisibility(View.GONE);
     }
 
     /**
@@ -164,7 +170,6 @@ class AccountPickerBottomSheetView implements BottomSheetContent {
         mLogoImage.setImageResource(R.drawable.location_bar_incognito_badge);
         mIncognitoInterstitialView.setVisibility(View.VISIBLE);
 
-        mAccountPickerTitle.setVisibility(View.GONE);
         mAccountPickerSubtitle.setVisibility(View.GONE);
         mHorizontalDivider.setVisibility(View.GONE);
         mAccountListView.setVisibility(View.GONE);

chrome/android/javatests/src/org/chromium/chrome/browser/signin/AccountPickerBottomSheetRenderTest.java

@@ -6,6 +6,8 @@ package org.chromium.chrome.browser.signin;
 
 import static androidx.test.espresso.Espresso.onView;
 import static androidx.test.espresso.action.ViewActions.click;
+import static androidx.test.espresso.action.ViewActions.pressBack;
+import static androidx.test.espresso.matcher.ViewMatchers.isRoot;
 import static androidx.test.espresso.matcher.ViewMatchers.withText;
 
 import static org.mockito.ArgumentMatchers.any;
@@ -133,6 +135,21 @@ public class AccountPickerBottomSheetRenderTest {
         mRenderTestRule.render(mCoordinator.getBottomSheetViewForTesting(), "expanded_sheet");
     }
 
+    @Test
+    @MediumTest
+    @Feature("RenderTest")
+    @ParameterAnnotations.UseMethodParameter(NightModeTestUtils.NightModeParams.class)
+    public void testExpandedSheetShowsWhenBackpressingOnIncognitoInterstitial(
+            boolean nightModeEnabled) throws IOException {
+        mAccountManagerTestRule.addAccount(PROFILE_DATA1);
+        mAccountManagerTestRule.addAccount(PROFILE_DATA2);
+        buildAndShowCollapsedBottomSheet();
+        onView(withText(PROFILE_DATA1.getFullName())).perform(click());
+        onView(withText(R.string.signin_incognito_mode_primary)).perform(click());
+        onView(isRoot()).perform(pressBack());
+        mRenderTestRule.render(mCoordinator.getBottomSheetViewForTesting(), "expanded_sheet");
+    }
+
     @Test
     @MediumTest
     @Feature("RenderTest")

chrome/android/javatests/src/org/chromium/chrome/browser/signin/AccountPickerBottomSheetTest.java

@@ -183,6 +183,28 @@ public class AccountPickerBottomSheetTest {
         checkCollapsedAccountList(PROFILE_DATA1);
     }
 
+    @Test
+    @MediumTest
+    public void testExpandedSheetShowsWhenBackpressingOnIncognitoInterstitial() {
+        buildAndShowExpandedBottomSheet();
+        onView(withText(R.string.signin_incognito_mode_primary)).perform(click());
+        onView(isRoot()).perform(pressBack());
+
+        onView(withText(R.string.signin_account_picker_dialog_title)).check(matches(isDisplayed()));
+        onView(withText(R.string.signin_account_picker_bottom_sheet_subtitle))
+                .check(matches(isDisplayed()));
+        onView(withId(R.id.account_picker_horizontal_divider)).check(matches(isDisplayed()));
+        onView(allOf(withText(PROFILE_DATA1.getAccountName()), withEffectiveVisibility(VISIBLE)))
+                .check(matches(isDisplayed()));
+        onView(allOf(withText(PROFILE_DATA1.getFullName()), withEffectiveVisibility(VISIBLE)))
+                .check(matches(isDisplayed()));
+        onView(withText(PROFILE_DATA2.getAccountName())).check(matches(isDisplayed()));
+        onView(withText(R.string.signin_add_account_to_device)).check(matches(isDisplayed()));
+
+        onView(withId(R.id.account_picker_selected_account)).check(matches(not(isDisplayed())));
+        onView(withId(R.id.account_picker_continue_as_button)).check(matches(not(isDisplayed())));
+    }
+
     @Test
     @MediumTest
     public void testAccountDisappearedOnCollapsedSheet() {
@@ -387,7 +409,7 @@ public class AccountPickerBottomSheetTest {
 
     private void checkIncognitoInterstitialSheet() {
         onView(withId(R.id.account_picker_bottom_sheet_logo)).check(matches(isDisplayed()));
-        onView(withId(R.id.account_picker_bottom_sheet_title)).check(matches(not(isDisplayed())));
+        onView(withId(R.id.account_picker_bottom_sheet_title)).check(matches(isDisplayed()));
         onView(withId(R.id.account_picker_bottom_sheet_subtitle))
                 .check(matches(not(isDisplayed())));
         onView(withId(R.id.account_picker_horizontal_divider)).check(matches(not(isDisplayed())));