[Autofill Assistant] Fixed crash caused by TouchEventFilter when interacting...

[Autofill Assistant] Fixed crash caused by TouchEventFilter when interacting with page after autofill assistant has given up.

The crash was caused by listeners that were not properly unregistered.

Bug: 806868
Change-Id: Id7514b6a1c6a2a6e97ecf57b4eb4c6812ed1cb4e
Reviewed-on: https://chromium-review.googlesource.com/c/1344103Reviewed-by: Stephane Zermatten <szermatt@chromium.org>
Commit-Queue: Clemens Arbesser <arbesser@google.com>
Cr-Commit-Position: refs/heads/master@{#609740}

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

@@ -238,8 +238,6 @@ class AutofillAssistantUiDelegate {
                                  .findViewById(R.id.autofill_assistant);
         // TODO(crbug.com/806868): Set hint text on overlay.
         mTouchEventFilter = (TouchEventFilter) mFullContainer.findViewById(R.id.touch_event_filter);
-        mTouchEventFilter.init(client, activity.getFullscreenManager(),
-                activity.getActivityTab().getWebContents());
         mBottomBar = mFullContainer.findViewById(R.id.bottombar);
         mBottomBar.findViewById(R.id.close_button)
                 .setOnClickListener(unusedView -> mClient.onDismiss());
@@ -403,6 +401,8 @@ class AutofillAssistantUiDelegate {
 
     public void show() {
         if (mFullContainer.getVisibility() != View.VISIBLE) {
+            mTouchEventFilter.init(mClient, mActivity.getFullscreenManager(),
+                    mActivity.getActivityTab().getWebContents());
             mFullContainer.setVisibility(View.VISIBLE);
 
             // Set the initial progress. It is OK to make multiple calls to this method as it will
@@ -412,6 +412,7 @@ class AutofillAssistantUiDelegate {
     }
 
     public void hide() {
+        mTouchEventFilter.deInit();
         mFullContainer.setVisibility(View.GONE);
     }
 

chrome/android/java/src/org/chromium/chrome/browser/autofill_assistant/ui/TouchEventFilter.java

@@ -66,6 +66,7 @@ public class TouchEventFilter
 
     private Client mClient;
     private ChromeFullscreenManager mFullscreenManager;
+    private GestureListenerManager mGestureListenerManager;
     private final List<RectF> mTouchableArea = new ArrayList<>();
     private final Paint mGrayOut;
     private final Paint mClear;
@@ -174,7 +175,20 @@ public class TouchEventFilter
         mClient = client;
         mFullscreenManager = fullscreenManager;
         mFullscreenManager.addListener(this);
-        GestureListenerManager.fromWebContents(webContents).addListener(this);
+        mGestureListenerManager = GestureListenerManager.fromWebContents(webContents);
+        mGestureListenerManager.addListener(this);
+    }
+
+    public void deInit() {
+        mClient = null;
+        if (mFullscreenManager != null) {
+            mFullscreenManager.removeListener(this);
+            mFullscreenManager = null;
+        }
+        if (mGestureListenerManager != null) {
+            mGestureListenerManager.removeListener(this);
+            mGestureListenerManager = null;
+        }
     }
 
     /** Sets the color to be used for unusable areas. */