[Autofill Assistant] Slim down AutofillAssistantUiController.

This patch take out initialization and delayed shutdown from
AutofillAssistantUiController:

 * initialization goes into a new class AutofillAssistantFacade, called
   from CustomTabActivity.

 * UiDelegateHolder becomes a toplevel class, responsible for delayed
   shutdown and UI pausing

The following responsibilities remain in AutofillAssistantUiController:

 * bridging Java -> C++ and C++ -> Java
 * account management and authentication

This patch also unifies the way the "give up" message is displayed in
Java, removes the unnecessary C++ OnGiveUp method and always hides the
overlay and the event filter when switching to graceful shutdown mode.

Bug: 806868
Change-Id: Idef806520f5e6e8a6dda4fc843d61bf77c1eafb4
Reviewed-on: https://chromium-review.googlesource.com/c/1333652
Commit-Queue: Stephane Zermatten <szermatt@chromium.org>
Reviewed-by: Egor Pasko <pasko@chromium.org>
Reviewed-by: Mathias Carlen <mcarlen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608007}

chrome/android/java/src/org/chromium/chrome/browser/autofill_assistant/AutofillAssistantFacade.java

+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.autofill_assistant;
+
+import android.os.Bundle;
+
+import org.chromium.base.ContextUtils;
+import org.chromium.chrome.browser.customtabs.CustomTabActivity;
+import org.chromium.chrome.browser.preferences.autofill_assistant.AutofillAssistantPreferences;
+import org.chromium.chrome.browser.tab.EmptyTabObserver;
+import org.chromium.chrome.browser.tab.Tab;
+import org.chromium.chrome.browser.tabmodel.EmptyTabModelObserver;
+import org.chromium.chrome.browser.tabmodel.TabModel;
+import org.chromium.chrome.browser.tabmodel.TabModel.TabSelectionType;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Locale;
+import java.util.Map;
+
+/** Facade for starting Autofill Assistant on a custom tab. */
+public class AutofillAssistantFacade {
+    private static final String RFC_3339_FORMAT_WITHOUT_TIMEZONE = "yyyy'-'MM'-'dd'T'HH':'mm':'ss";
+
+    /** Prefix for Intent extras relevant to this feature. */
+    private static final String INTENT_EXTRA_PREFIX =
+            "org.chromium.chrome.browser.autofill_assistant.";
+
+    /** Autofill Assistant Study name. */
+    private static final String STUDY_NAME = "AutofillAssistant";
+
+    /** Variation url parameter name. */
+    private static final String URL_PARAMETER_NAME = "url";
+
+    /** Special parameter that enables the feature. */
+    private static final String PARAMETER_ENABLED = "ENABLED";
+
+    /** Returns true if all conditions are satisfied to start Autofill Assistant. */
+    public static boolean isConfigured(Bundle intentExtras) {
+        return getBooleanParameter(intentExtras, PARAMETER_ENABLED)
+                && !AutofillAssistantStudy.getUrl().isEmpty()
+                && ContextUtils.getAppSharedPreferences().getBoolean(
+                           AutofillAssistantPreferences.PREF_AUTOFILL_ASSISTANT_SWITCH, true);
+    }
+
+    /** Starts Autofill Assistant on the given {@code activity}. */
+    public static void start(CustomTabActivity activity) {
+        Map<String, String> parameters = extractParameters(activity.getInitialIntent().getExtras());
+        parameters.remove(PARAMETER_ENABLED);
+
+        AutofillAssistantUiController controller =
+                new AutofillAssistantUiController(activity, parameters);
+        AutofillAssistantUiDelegate uiDelegate =
+                new AutofillAssistantUiDelegate(activity, controller);
+        UiDelegateHolder delegateHolder = new UiDelegateHolder(controller, uiDelegate);
+        controller.setUiDelegateHolder(delegateHolder);
+        initTabObservers(activity, delegateHolder);
+
+        AutofillAssistantUiDelegate.Details initialDetails = makeDetailsFromParameters(parameters);
+        controller.maybeUpdateDetails(initialDetails);
+
+        uiDelegate.startOrSkipInitScreen();
+    }
+
+    private static void initTabObservers(
+            CustomTabActivity activity, UiDelegateHolder delegateHolder) {
+        // Shut down Autofill Assistant when the tab is detached from the activity.
+        Tab activityTab = activity.getActivityTab();
+        activityTab.addObserver(new EmptyTabObserver() {
+            @Override
+            public void onActivityAttachmentChanged(Tab tab, boolean isAttached) {
+                if (!isAttached) {
+                    activityTab.removeObserver(this);
+                    delegateHolder.shutdown();
+                }
+            }
+        });
+
+        // Shut down Autofill Assistant when the selected tab (foreground tab) is changed.
+        TabModel currentTabModel = activity.getTabModelSelector().getCurrentModel();
+        currentTabModel.addObserver(new EmptyTabModelObserver() {
+            @Override
+            public void didSelectTab(Tab tab, @TabSelectionType int type, int lastId) {
+                currentTabModel.removeObserver(this);
+                delegateHolder.giveUp();
+            }
+        });
+    }
+
+    /** Return the value if the given boolean parameter from the extras. */
+    private static boolean getBooleanParameter(Bundle extras, String parameterName) {
+        return extras.getBoolean(INTENT_EXTRA_PREFIX + parameterName, false);
+    }
+
+    /** Returns a map containing the extras starting with {@link #INTENT_EXTRA_PREFIX}. */
+    private static Map<String, String> extractParameters(Bundle extras) {
+        Map<String, String> result = new HashMap<>();
+        for (String key : extras.keySet()) {
+            if (key.startsWith(INTENT_EXTRA_PREFIX)) {
+                result.put(key.substring(INTENT_EXTRA_PREFIX.length()), extras.get(key).toString());
+            }
+        }
+        return result;
+    }
+
+    // TODO(crbug.com/806868): Create a fallback when there are no parameters for details.
+    // TODO(crbug.com/806868): Create a fallback when there are no parameters for details.
+    private static AutofillAssistantUiDelegate.Details makeDetailsFromParameters(
+            Map<String, String> parameters) {
+        String title = "";
+        String description = "";
+        Date date = null;
+        for (String key : parameters.keySet()) {
+            if (key.contains("E_NAME")) {
+                title = parameters.get(key);
+                continue;
+            }
+
+            if (key.contains("R_NAME")) {
+                description = parameters.get(key);
+                continue;
+            }
+
+            if (key.contains("DATETIME")) {
+                try {
+                    // The parameter contains the timezone shift from the current location, that we
+                    // don't care about.
+                    date = new SimpleDateFormat(RFC_3339_FORMAT_WITHOUT_TIMEZONE, Locale.ROOT)
+                                   .parse(parameters.get(key));
+                } catch (ParseException e) {
+                    // Ignore.
+                }
+            }
+        }
+
+        return new AutofillAssistantUiDelegate.Details(
+                title, /* url= */ "", date, description, /* isFinal= */ false);
+    }
+}

chrome/android/java/src/org/chromium/chrome/browser/autofill_assistant/AutofillAssistantUiController.java

@@ -11,37 +11,22 @@ import android.os.Bundle;
 import android.support.annotation.Nullable;
 import android.telephony.TelephonyManager;
 
-import org.chromium.base.Callback;
 import org.chromium.base.ContextUtils;
 import org.chromium.base.LocaleUtils;
-import org.chromium.base.ThreadUtils;
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.JNINamespace;
 import org.chromium.chrome.autofill_assistant.R;
 import org.chromium.chrome.browser.autofill.PersonalDataManager;
 import org.chromium.chrome.browser.customtabs.CustomTabActivity;
-import org.chromium.chrome.browser.preferences.autofill_assistant.AutofillAssistantPreferences;
-import org.chromium.chrome.browser.snackbar.SnackbarManager;
-import org.chromium.chrome.browser.tab.EmptyTabObserver;
-import org.chromium.chrome.browser.tab.Tab;
-import org.chromium.chrome.browser.tabmodel.EmptyTabModelObserver;
-import org.chromium.chrome.browser.tabmodel.TabModel;
-import org.chromium.chrome.browser.tabmodel.TabModel.TabSelectionType;
 import org.chromium.components.signin.AccountManagerFacade;
 import org.chromium.content_public.browser.WebContents;
 import org.chromium.payments.mojom.PaymentOptions;
 
-import java.text.ParseException;
-import java.text.SimpleDateFormat;
-import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Calendar;
 import java.util.Date;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Locale;
 import java.util.Map;
-import java.util.Queue;
 
 /**
  * Bridge to native side autofill_assistant::UiControllerAndroid. It allows native side to control
@@ -60,25 +45,19 @@ public class AutofillAssistantUiController implements AutofillAssistantUiDelegat
     private static final String AUTH_TOKEN_TYPE =
             "oauth2:https://www.googleapis.com/auth/userinfo.profile";
 
-    /** Display the final message for that long before shutting everything down. */
-    private static final long GRACEFUL_SHUTDOWN_DELAY_MS = 5000;
-
-    private static final String RFC_3339_FORMAT_WITHOUT_TIMEZONE = "yyyy'-'MM'-'dd'T'HH':'mm':'ss";
-
     private final WebContents mWebContents;
-    private final UiDelegateHolder mUiDelegateHolder;
     private final String mInitialUrl;
 
     // TODO(crbug.com/806868): Move mCurrentDetails and mStatusMessage to a Model (refactor to MVC).
-    AutofillAssistantUiDelegate.Details mCurrentDetails =
+    private AutofillAssistantUiDelegate.Details mCurrentDetails =
             AutofillAssistantUiDelegate.Details.getEmptyDetails();
     private String mStatusMessage;
 
-    /**
-     * Native pointer to the UIController.
-     */
+    /** Native pointer to the UIController. */
     private final long mUiControllerAndroid;
 
+    private UiDelegateHolder mUiDelegateHolder;
+
     /**
      * Indicates whether {@link mAccount} has been initialized.
      */
@@ -95,71 +74,31 @@ public class AutofillAssistantUiController implements AutofillAssistantUiDelegat
     /** If set, fetch the access token once the accounts are fetched. */
     private boolean mShouldFetchAccessToken;
 
-    /**
-     * Returns true if all conditions are satisfied to construct an AutofillAssistantUiController.
-     *
-     * @return True if a controller can be constructed.
-     */
-    public static boolean isConfigured(Bundle intentExtras) {
-        return getBooleanParameter(intentExtras, PARAMETER_ENABLED)
-                && !AutofillAssistantStudy.getUrl().isEmpty()
-                && ContextUtils.getAppSharedPreferences().getBoolean(
-                           AutofillAssistantPreferences.PREF_AUTOFILL_ASSISTANT_SWITCH, true);
-    }
-
-    @Override
-    public void onInitOk() {
-        nativeStart(mUiControllerAndroid, mInitialUrl);
-    }
-
     /**
      * Construct Autofill Assistant UI controller.
      *
      * @param activity The CustomTabActivity of the controller associated with.
      */
-    public AutofillAssistantUiController(CustomTabActivity activity) {
-        // Set mUiDelegate before nativeInit, as it can be accessed through native methods from
-        // nativeInit already.
-        mUiDelegateHolder = new UiDelegateHolder(new AutofillAssistantUiDelegate(activity, this));
-        chooseAccountAsync(activity.getInitialIntent().getExtras());
-
-        Map<String, String> parameters = extractParameters(activity.getInitialIntent().getExtras());
-        parameters.remove(PARAMETER_ENABLED);
-
-        maybeUpdateDetails(makeDetailsFromParameters(parameters));
-
-        Tab activityTab = activity.getActivityTab();
-        mWebContents = activityTab.getWebContents();
+    public AutofillAssistantUiController(
+            CustomTabActivity activity, Map<String, String> parameters) {
+        mWebContents = activity.getActivityTab().getWebContents();
         mInitialUrl = activity.getInitialIntent().getDataString();
-
         mUiControllerAndroid =
                 nativeInit(mWebContents, parameters.keySet().toArray(new String[parameters.size()]),
                         parameters.values().toArray(new String[parameters.size()]),
                         LocaleUtils.getDefaultLocaleString(), getCountryIso());
 
-        mUiDelegateHolder.performUiOperation(uiDelegate -> uiDelegate.startOrSkipInitScreen());
-
-        // Shut down Autofill Assistant when the tab is detached from the activity.
-        activityTab.addObserver(new EmptyTabObserver() {
-            @Override
-            public void onActivityAttachmentChanged(Tab tab, boolean isAttached) {
-                if (!isAttached) {
-                    activityTab.removeObserver(this);
-                    mUiDelegateHolder.shutdown();
+        chooseAccountAsync(activity.getInitialIntent().getExtras());
     }
+
+    void setUiDelegateHolder(UiDelegateHolder uiDelegateHolder) {
+        mUiDelegateHolder = uiDelegateHolder;
     }
-        });
 
-        // Shut down Autofill Assistant when the selected tab (foreground tab) is changed.
-        TabModel currentTabModel = activity.getTabModelSelector().getCurrentModel();
-        currentTabModel.addObserver(new EmptyTabModelObserver() {
     @Override
-            public void didSelectTab(Tab tab, @TabSelectionType int type, int lastId) {
-                currentTabModel.removeObserver(this);
-
-                nativeGiveUp(mUiControllerAndroid);
-            }
-        });
+    public void onInitOk() {
+        assert mUiDelegateHolder != null;
+        nativeStart(mUiControllerAndroid, mInitialUrl);
     }
 
     @Override
@@ -202,60 +141,25 @@ public class AutofillAssistantUiController implements AutofillAssistantUiDelegat
         return nativeOnRequestDebugContext(mUiControllerAndroid);
     }
 
-    /** Return the value if the given boolean parameter from the extras. */
-    private static boolean getBooleanParameter(Bundle extras, String parameterName) {
-        return extras.getBoolean(INTENT_EXTRA_PREFIX + parameterName, false);
-    }
-
-    /** Returns a map containing the extras starting with {@link #INTENT_EXTRA_PREFIX}. */
-    private static Map<String, String> extractParameters(Bundle extras) {
-        Map<String, String> result = new HashMap<>();
-        for (String key : extras.keySet()) {
-            if (key.startsWith(INTENT_EXTRA_PREFIX)) {
-                result.put(key.substring(INTENT_EXTRA_PREFIX.length()), extras.get(key).toString());
-            }
-        }
-        return result;
-    }
-
-    // TODO(crbug.com/806868): Create a fallback when there are no parameters for details.
-    private static AutofillAssistantUiDelegate.Details makeDetailsFromParameters(
-            Map<String, String> parameters) {
-        String title = "";
-        String description = "";
-        Date date = null;
-        for (String key : parameters.keySet()) {
-            if (key.contains("E_NAME")) {
-                title = parameters.get(key);
-                continue;
-            }
-
-            if (key.contains("R_NAME")) {
-                description = parameters.get(key);
-                continue;
-            }
-
-            if (key.contains("DATETIME")) {
-                try {
-                    // The parameter contains the timezone shift from the current location, that we
-                    // don't care about.
-                    date = new SimpleDateFormat(RFC_3339_FORMAT_WITHOUT_TIMEZONE, Locale.ROOT)
-                                   .parse(parameters.get(key));
-                } catch (ParseException e) {
-                    // Ignore.
-                }
-            }
-        }
-
-        return new AutofillAssistantUiDelegate.Details(
-                title, /* url= */ "", date, description, /* isFinal= */ false);
-    }
-
     @Override
     public void onClickOverlay() {
         // TODO(crbug.com/806868): Notify native side.
     }
 
+    /**
+     * Immediately and unconditionally destroys the UI Controller.
+     *
+     * <p>Call {@link UiDelegateHolder#shutdown} to shutdown Autofill Assistant properly and safely.
+     *
+     * <p>Destroy is different from shutdown in that {@code unsafeDestroy} just deletes the native
+     * controller and all the objects it owns, without changing the state of the UI. When that
+     * happens, everything stops irrevocably on the native side. Doing this at the wrong time will
+     * cause crashes.
+     */
+    void unsafeDestroy() {
+        nativeDestroy(mUiControllerAndroid);
+    }
+
     @CalledByNative
     private void onShowStatusMessage(String message) {
         mStatusMessage = message;
@@ -349,9 +253,7 @@ public class AutofillAssistantUiController implements AutofillAssistantUiDelegat
                             // A failed payment request flow indicates that the UI was either
                             // dismissed or the back button was clicked. In that case we gracefully
                             // shut down.
-                            onHideOverlay();
-                            uiDelegate.showGiveUpMessage();
-                            onShutdownGracefully();
+                            mUiDelegateHolder.giveUp();
                         }
                     }));
         });
@@ -362,7 +264,7 @@ public class AutofillAssistantUiController implements AutofillAssistantUiDelegat
      *
      * @return false if details were rejected.
      */
-    private boolean maybeUpdateDetails(AutofillAssistantUiDelegate.Details newDetails) {
+    boolean maybeUpdateDetails(AutofillAssistantUiDelegate.Details newDetails) {
         if (!mCurrentDetails.isSimilarTo(newDetails)) {
             return false;
         }
@@ -422,131 +324,6 @@ public class AutofillAssistantUiController implements AutofillAssistantUiDelegat
                 uiDelegate -> { uiDelegate.updateTouchableArea(enabled, boxes); });
     }
 
-    /**
-     * Class holder for the AutofillAssistantUiDelegate to make sure we don't make UI changes when
-     * we are in a pause state (i.e. few seconds before stopping completely).
-     */
-    private class UiDelegateHolder {
-        private final AutofillAssistantUiDelegate mUiDelegate;
-
-        private boolean mShouldQueueUiOperations = false;
-        private boolean mHasBeenShutdown = false;
-        private boolean mIsShuttingDown = false;
-        private SnackbarManager.SnackbarController mDismissSnackbar;
-        private final Queue<Callback<AutofillAssistantUiDelegate>> mPendingUiOperations =
-                new ArrayDeque<>();
-
-        private UiDelegateHolder(AutofillAssistantUiDelegate uiDelegate) {
-            mUiDelegate = uiDelegate;
-        }
-
-        /**
-         * Perform a UI operation:
-         *  - directly if we are not in a pause state.
-         *  - later if the shutdown is cancelled.
-         *  - never if Autofill Assistant is shut down.
-         */
-        public void performUiOperation(Callback<AutofillAssistantUiDelegate> operation) {
-            if (mHasBeenShutdown || mIsShuttingDown) {
-                return;
-            }
-
-            if (mShouldQueueUiOperations) {
-                mPendingUiOperations.add(operation);
-                return;
-            }
-
-            operation.onResult(mUiDelegate);
-        }
-
-        /**
-         * Handles the dismiss operation.
-         *
-         * In normal mode, hides the UI, pauses UI operations and, unless undone within the time
-         * delay, eventually destroy everything. In graceful shutdown mode, shutdown immediately.
-         */
-        public void dismiss(int stringResourceId, Object... formatArgs) {
-            assert !mHasBeenShutdown;
-
-            if (mIsShuttingDown) {
-                shutdown();
-                return;
-            }
-
-            if (mDismissSnackbar != null) {
-                // Remove duplicate calls.
-                return;
-            }
-
-            pauseUiOperations();
-            mUiDelegate.hide();
-            mDismissSnackbar = new SnackbarManager.SnackbarController() {
-                @Override
-                public void onAction(Object actionData) {
-                    // Shutdown was cancelled.
-                    mDismissSnackbar = null;
-                    mUiDelegate.show();
-                    unpauseUiOperations();
-                }
-
-                @Override
-                public void onDismissNoAction(Object actionData) {
-                    shutdown();
-                }
-            };
-            mUiDelegate.showAutofillAssistantStoppedSnackbar(
-                    mDismissSnackbar, stringResourceId, formatArgs);
-        }
-
-        /** Enters graceful shutdown mode once we can again perform UI operations. */
-        public void enterGracefulShutdownMode() {
-            mUiDelegateHolder.performUiOperation(uiDelegate -> {
-                mIsShuttingDown = true;
-                mPendingUiOperations.clear();
-                uiDelegate.enterGracefulShutdownMode();
-                ThreadUtils.postOnUiThreadDelayed(this ::shutdown, GRACEFUL_SHUTDOWN_DELAY_MS);
-            });
-        }
-
-        /**
-         * Hides the UI and destroys everything.
-         *
-         * <p>Shutdown is final: After this call from the C++ side, as it's been deleted and no UI
-         * operation can run.
-         */
-        public void shutdown() {
-            if (mHasBeenShutdown) {
-                return;
-            }
-
-            mHasBeenShutdown = true;
-            mPendingUiOperations.clear();
-            if (mDismissSnackbar != null) {
-                mUiDelegate.dismissSnackbar(mDismissSnackbar);
-            }
-            mUiDelegate.hide();
-            nativeDestroy(mUiControllerAndroid);
-        }
-
-        /**
-         * Pause all UI operations such that they can potentially be ran later using {@link
-         * #unpauseUiOperations()}.
-         */
-        private void pauseUiOperations() {
-            mShouldQueueUiOperations = true;
-        }
-
-        /**
-         * Unpause and trigger all UI operations received by {@link #performUiOperation(Callback)}
-         * since the last {@link #pauseUiOperations()}.
-         */
-        private void unpauseUiOperations() {
-            mShouldQueueUiOperations = false;
-            while (!mPendingUiOperations.isEmpty()) {
-                mPendingUiOperations.remove().onResult(mUiDelegate);
-            }
-        }
-    }
 
     @CalledByNative
     private void fetchAccessToken() {
@@ -656,7 +433,6 @@ public class AutofillAssistantUiController implements AutofillAssistantUiDelegat
             String[] parameterValues, String locale, String countryCode);
     private native void nativeStart(long nativeUiControllerAndroid, String initialUrl);
     private native void nativeDestroy(long nativeUiControllerAndroid);
-    private native void nativeGiveUp(long nativeUiControllerAndroid);
     private native void nativeOnScriptSelected(long nativeUiControllerAndroid, String scriptPath);
     private native void nativeOnAddressSelected(long nativeUiControllerAndroid, String guid);
     private native void nativeOnCardSelected(long nativeUiControllerAndroid, String guid);

chrome/android/java/src/org/chromium/chrome/browser/autofill_assistant/AutofillAssistantUiDelegate.java

@@ -523,6 +523,8 @@ class AutofillAssistantUiDelegate {
         // hacks to give enough space to display long messages.
         mStatusMessageView.setMaxLines(4);
         mBottomBar.findViewById(R.id.feedback_button).setVisibility(View.GONE);
+        hideOverlay();
+        mTouchEventFilter.setVisibility(View.GONE);
         hideProgressBar();
         hideDetails();
         mBottomBarAnimations.hideCarousel();

chrome/android/java/src/org/chromium/chrome/browser/autofill_assistant/UiDelegateHolder.java

+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.autofill_assistant;
+
+import org.chromium.base.Callback;
+import org.chromium.base.ThreadUtils;
+import org.chromium.chrome.browser.snackbar.SnackbarManager;
+
+import java.util.ArrayDeque;
+import java.util.Queue;
+
+/**
+ * Class holder for the AutofillAssistantUiDelegate to make sure we don't make UI changes when
+ * we are in a pause state (i.e. few seconds before stopping completely).
+ */
+class UiDelegateHolder {
+    /** Display the final message for that long before shutting everything down. */
+    private static final long GRACEFUL_SHUTDOWN_DELAY_MS = 5_000;
+
+    private final AutofillAssistantUiController mUiController;
+    private final AutofillAssistantUiDelegate mUiDelegate;
+
+    private boolean mPaused;
+    private boolean mHasBeenShutdown;
+    private boolean mIsShuttingDown;
+    private SnackbarManager.SnackbarController mDismissSnackbar;
+    private final Queue<Callback<AutofillAssistantUiDelegate>> mPendingUiOperations =
+            new ArrayDeque<>();
+
+    UiDelegateHolder(
+            AutofillAssistantUiController controller, AutofillAssistantUiDelegate uiDelegate) {
+        mUiController = controller;
+        mUiDelegate = uiDelegate;
+    }
+
+    /**
+     * Perform a UI operation:
+     *  - directly if we are not in a pause state.
+     *  - later if the shutdown is cancelled.
+     *  - never if Autofill Assistant is shut down.
+     */
+    void performUiOperation(Callback<AutofillAssistantUiDelegate> operation) {
+        if (mHasBeenShutdown || mIsShuttingDown) {
+            return;
+        }
+
+        if (mPaused) {
+            mPendingUiOperations.add(operation);
+            return;
+        }
+
+        operation.onResult(mUiDelegate);
+    }
+
+    /**
+     * Handles the dismiss operation.
+     *
+     * In normal mode, hides the UI, pauses UI operations and, unless undone within the time
+     * delay, eventually destroy everything. In graceful shutdown mode, shutdown immediately.
+     */
+    void dismiss(int stringResourceId, Object... formatArgs) {
+        assert !mHasBeenShutdown;
+
+        if (mIsShuttingDown) {
+            shutdown();
+            return;
+        }
+
+        if (mDismissSnackbar != null) {
+            // Remove duplicate calls.
+            return;
+        }
+
+        pauseUiOperations();
+        mUiDelegate.hide();
+        mDismissSnackbar = new SnackbarManager.SnackbarController() {
+            @Override
+            public void onAction(Object actionData) {
+                // Shutdown was cancelled.
+                mDismissSnackbar = null;
+                mUiDelegate.show();
+                unpauseUiOperations();
+            }
+
+            @Override
+            public void onDismissNoAction(Object actionData) {
+                shutdown();
+            }
+        };
+        mUiDelegate.showAutofillAssistantStoppedSnackbar(
+                mDismissSnackbar, stringResourceId, formatArgs);
+    }
+
+    /** Displays the give up message and enter graceful shutdown mode. */
+    void giveUp() {
+        performUiOperation(uiDelegate -> uiDelegate.showGiveUpMessage());
+        enterGracefulShutdownMode();
+    }
+
+    /** Enters graceful shutdown mode once we can again perform UI operations. */
+    void enterGracefulShutdownMode() {
+        performUiOperation(uiDelegate -> {
+            mIsShuttingDown = true;
+            mPendingUiOperations.clear();
+            uiDelegate.enterGracefulShutdownMode();
+            ThreadUtils.postOnUiThreadDelayed(this ::shutdown, GRACEFUL_SHUTDOWN_DELAY_MS);
+        });
+    }
+
+    /**
+     * Hides the UI and destroys everything.
+     *
+     * <p>Shutdown is final: After this call from the C++ side, as it's been deleted and no UI
+     * operation can run.
+     */
+    void shutdown() {
+        if (mHasBeenShutdown) {
+            return;
+        }
+
+        mHasBeenShutdown = true;
+        mPendingUiOperations.clear();
+        if (mDismissSnackbar != null) {
+            mUiDelegate.dismissSnackbar(mDismissSnackbar);
+        }
+        mUiDelegate.hide();
+        mUiController.unsafeDestroy();
+    }
+
+    /**
+     * Pause all UI operations such that they can potentially be ran later using {@link
+     * #unpauseUiOperations()}.
+     */
+    private void pauseUiOperations() {
+        mPaused = true;
+    }
+
+    /**
+     * Unpause and trigger all UI operations received by {@link #performUiOperation(Callback)}
+     * since the last {@link #pauseUiOperations()}.
+     */
+    private void unpauseUiOperations() {
+        mPaused = false;
+        while (!mPendingUiOperations.isEmpty()) {
+            mPendingUiOperations.remove().onResult(mUiDelegate);
+        }
+    }
+}

chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabActivity.java

@@ -63,7 +63,7 @@ import org.chromium.chrome.browser.ServiceTabLauncher;
 import org.chromium.chrome.browser.WarmupManager;
 import org.chromium.chrome.browser.WebContentsFactory;
 import org.chromium.chrome.browser.appmenu.AppMenuPropertiesDelegate;
-import org.chromium.chrome.browser.autofill_assistant.AutofillAssistantUiController;
+import org.chromium.chrome.browser.autofill_assistant.AutofillAssistantFacade;
 import org.chromium.chrome.browser.browserservices.BrowserSessionContentHandler;
 import org.chromium.chrome.browser.browserservices.BrowserSessionContentUtils;
 import org.chromium.chrome.browser.browserservices.PostMessageHandler;
@@ -189,8 +189,6 @@ public class CustomTabActivity extends ChromeActivity<CustomTabActivityComponent
 
     private WebappCustomTabTimeSpentLogger mWebappTimeSpentLogger;
 
-    private AutofillAssistantUiController mAutofillAssistantUiController;
-
     @Nullable
     private ModuleEntryPoint mModuleEntryPoint;
     @Nullable
@@ -700,10 +698,9 @@ public class CustomTabActivity extends ChromeActivity<CustomTabActivityComponent
                     getActivityTab().getWebContents());
         }
 
-        if (mAutofillAssistantUiController == null
-                && ChromeFeatureList.isEnabled(ChromeFeatureList.AUTOFILL_ASSISTANT)
-                && AutofillAssistantUiController.isConfigured(getInitialIntent().getExtras())) {
-            mAutofillAssistantUiController = new AutofillAssistantUiController(this);
+        if (ChromeFeatureList.isEnabled(ChromeFeatureList.AUTOFILL_ASSISTANT)
+                && AutofillAssistantFacade.isConfigured(getInitialIntent().getExtras())) {
+            AutofillAssistantFacade.start(this);
         }
 
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP && useSeparateTask()) {

chrome/android/java_sources.gni

@@ -120,12 +120,14 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/autofill/keyboard_accessory/PasswordAccessorySheetCoordinator.java",
   "java/src/org/chromium/chrome/browser/autofill/keyboard_accessory/PasswordAccessorySheetViewBinder.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/AnimatedProgressBar.java",
+  "java/src/org/chromium/chrome/browser/autofill_assistant/AutofillAssistantFacade.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/AutofillAssistantPaymentRequest.java",
+  "java/src/org/chromium/chrome/browser/autofill_assistant/AutofillAssistantStudy.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/AutofillAssistantUiController.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/AutofillAssistantUiDelegate.java",
-  "java/src/org/chromium/chrome/browser/autofill_assistant/AutofillAssistantStudy.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/FeedbackContext.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/InitScreenController.java",
+  "java/src/org/chromium/chrome/browser/autofill_assistant/UiDelegateHolder.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/ui/BottomBarAnimations.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/ui/PaymentRequestBottomBar.java",
   "java/src/org/chromium/chrome/browser/autofill_assistant/ui/PaymentRequestUI.java",

chrome/browser/android/autofill_assistant/ui_controller_android.cc

@@ -404,12 +404,6 @@ void UiControllerAndroid::Destroy(JNIEnv* env,
   ui_delegate_->OnDestroy();
 }
 
-void UiControllerAndroid::GiveUp(
-    JNIEnv* env,
-    const base::android::JavaParamRef<jobject>& jcaller) {
-  ui_delegate_->OnGiveUp();
-}
-
 static jlong JNI_AutofillAssistantUiController_Init(
     JNIEnv* env,
     const JavaParamRef<jobject>& jcaller,

chrome/browser/android/autofill_assistant/ui_controller_android.h

@@ -77,7 +77,6 @@ class UiControllerAndroid : public UiController,
              const base::android::JavaParamRef<jobject>& jcaller,
              const base::android::JavaParamRef<jstring>& initialUrlString);
   void Destroy(JNIEnv* env, const base::android::JavaParamRef<jobject>& obj);
-  void GiveUp(JNIEnv* env, const base::android::JavaParamRef<jobject>& obj);
   void OnScriptSelected(
       JNIEnv* env,
       const base::android::JavaParamRef<jobject>& jcaller,

components/autofill_assistant/browser/controller.cc

@@ -274,6 +274,12 @@ void Controller::OnScriptExecuted(const std::string& script_path,
   GetOrCheckScripts(web_contents()->GetLastCommittedURL());
 }
 
+void Controller::GiveUp() {
+  GetUiController()->ShowStatusMessage(
+      l10n_util::GetStringUTF8(IDS_AUTOFILL_ASSISTANT_GIVE_UP));
+  GetUiController()->ShutdownGracefully();
+}
+
 void Controller::OnClickOverlay() {
   GetUiController()->HideOverlay();
   // TODO(crbug.com/806868): Stop executing scripts.
@@ -319,12 +325,6 @@ void Controller::OnDestroy() {
   delete this;
 }
 
-void Controller::OnGiveUp() {
-  GetUiController()->ShowStatusMessage(
-      l10n_util::GetStringUTF8(IDS_AUTOFILL_ASSISTANT_GIVE_UP));
-  GetUiController()->ShutdownGracefully();
-}
-
 void Controller::DidAttachInterstitialPage() {
   GetUiController()->Shutdown();
 }
@@ -360,9 +360,7 @@ void Controller::OnNoRunnableScriptsAnymore() {
 
   // We're navigated to a page that has no scripts or the scripts have reached a
   // state from which they cannot recover through a DOM change.
-  GetUiController()->ShowStatusMessage(
-      l10n_util::GetStringUTF8(IDS_AUTOFILL_ASSISTANT_GIVE_UP));
-  GetUiController()->ShutdownGracefully();
+  GiveUp();
   return;
 }
 
@@ -450,7 +448,7 @@ void Controller::DidStartNavigation(
       !script_tracker_->running() && !navigation_handle->WasServerRedirect() &&
       !navigation_handle->IsSameDocument() &&
       !navigation_handle->IsRendererInitiated()) {
-    OnGiveUp();
+    GiveUp();
     return;
   }
 }

components/autofill_assistant/browser/controller.h

@@ -80,12 +80,12 @@ class Controller : public ScriptExecutorDelegate,
   void StartPeriodicScriptChecks();
   void StopPeriodicScriptChecks();
   void OnPeriodicScriptCheck();
+  void GiveUp();
 
   // Overrides content::UiDelegate:
   void Start(const GURL& initialUrl) override;
   void OnClickOverlay() override;
   void OnDestroy() override;
-  void OnGiveUp() override;
   void OnScriptSelected(const std::string& script_path) override;
   std::string GetDebugContext() override;
 

components/autofill_assistant/browser/ui_delegate.h

@@ -23,11 +23,6 @@ class UiDelegate {
   // detached from the associated activity.
   virtual void OnDestroy() = 0;
 
-  // Called when the Autofill Assistant should display a message saying that
-  // it's shutting down and then shut down, because something happened that
-  // scripts cannot handle, such as a new window being opened.
-  virtual void OnGiveUp() = 0;
-
   // Called when a script was selected for execution.
   virtual void OnScriptSelected(const std::string& script_path) = 0;