Pull the Activity context from WindowAndroid if possible

ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java

Index: ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java
diff --git a/ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java b/ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java
index ad02b45884a08c9467fb8c7ead4a291f31a0a9e4..b2e9c465ea4416f77e2c249c6d59bbe11a197060 100644
--- a/ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java
+++ b/ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java
@@ -7,6 +7,7 @@ package org.chromium.ui.base;
 import android.app.Activity;
 import android.app.PendingIntent;
 import android.content.ActivityNotFoundException;
+import android.content.Context;
 import android.content.Intent;
 import android.content.IntentSender.SendIntentException;
 import android.content.SharedPreferences;
@@ -51,19 +52,23 @@ public class ActivityWindowAndroid
      * Creates an Activity-specific WindowAndroid with associated intent functionality.
      * TODO(jdduke): Remove this overload when all callsites have been updated to
      * indicate their activity state listening preference.
-     * @param activity The activity associated with the WindowAndroid.
+     * @param context Context wrapping an activity associated with the WindowAndroid.
      */
-    public ActivityWindowAndroid(Activity activity) {
-        this(activity, true);
+    public ActivityWindowAndroid(Context context) {
+        this(context, true);
     }
 
     /**
      * Creates an Activity-specific WindowAndroid with associated intent functionality.
-     * @param activity The activity associated with the WindowAndroid.
+     * @param context Context wrapping an activity associated with the WindowAndroid.
      * @param listenToActivityState Whether to listen to activity state changes.
      */
-    public ActivityWindowAndroid(Activity activity, boolean listenToActivityState) {
-        super(activity.getApplicationContext());
+    public ActivityWindowAndroid(Context context, boolean listenToActivityState) {
+        super(context);
+        Activity activity = activityFromContext(context);
+        if (activity == null) {
+            throw new IllegalArgumentException("Context is not and does not wrap an Activity");
+        }
         mActivityRef = new WeakReference<Activity>(activity);
         mHandler = new Handler();
         mOutstandingPermissionRequests = new SparseArray<PermissionCallback>();
@@ -209,8 +214,7 @@ public class ActivityWindowAndroid
 
     @Override
     public WeakReference<Activity> getActivity() {
-        // Return a new WeakReference to prevent clients from releasing our internal WeakReference.
-        return new WeakReference<Activity>(mActivityRef.get());
+        return new WeakReference<Activity>(activityFromContext(getContext().get()));
     }
 
     @Override