[DO NOT MERGE] Bring back overlay warning in permissions UI.

The package installer has a special event handling when
the user tries to interact with it and an overlay window
intersects the installer one. We show a warning that an
overlay was detected and point the user to settings. This
regressed and nothing happened when the users click the
allow button.

bug:28572707
bug:26677796

Change-Id: I617595e7cd5277576ccb9915946b77082a1c2b9e
(cherry picked from commit 92d61dd6)

res/layout/grant_permissions.xml

@@ -91,14 +91,14 @@
                     android:text="@string/grant_dialog_button_deny" >
                 </Button>
 
-                <com.android.packageinstaller.permission.ui.SecureButtonView
+                <Button
                     android:id="@+id/permission_allow_button"
                     android:layout_width="wrap_content"
                     android:layout_height="wrap_content"
                     style="?android:attr/buttonBarButtonStyle"
                     android:layout_marginStart="8dip"
                     android:text="@string/grant_dialog_button_allow" >
-                </com.android.packageinstaller.permission.ui.SecureButtonView>
+                </Button>
 
             </LinearLayout>
 

src/com/android/packageinstaller/permission/ui/OverlayTouchActivity.java

@@ -29,7 +29,8 @@ public class OverlayTouchActivity extends Activity {
 
     @Override
     public boolean dispatchTouchEvent(MotionEvent event) {
-        mObscuredTouch = (event.getFlags() & MotionEvent.FLAG_WINDOW_IS_OBSCURED) != 0;
+        mObscuredTouch = (event.getFlags() & (MotionEvent.FLAG_WINDOW_IS_OBSCURED
+                | MotionEvent.FLAG_WINDOW_IS_PARTIALLY_OBSCURED)) != 0;
         return super.dispatchTouchEvent(event);
     }
 

src/com/android/packageinstaller/permission/ui/SecureButtonView.java

-/*
- * Copyright (C) 2016 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.android.packageinstaller.permission.ui;
-
-import android.content.Context;
-import android.util.AttributeSet;
-import android.view.MotionEvent;
-import android.widget.Button;
-
-/**
- * Extension of Button that uses the hidden MotionEvent flag for partially obscured windows to
- * prevent tapjacking attacks.
- */
-public class SecureButtonView extends Button {
-
-    public SecureButtonView(Context context) {
-        this(context, null);
-    }
-
-    public SecureButtonView(Context context, AttributeSet attrs) {
-        this(context, attrs, 0);
-    }
-
-    public SecureButtonView(Context context, AttributeSet attrs, int defStyleAttr) {
-        this(context, attrs, defStyleAttr, 0);
-    }
-
-    public SecureButtonView(Context context, AttributeSet attrs, int defStyleAttr,
-            int defStyleRes) {
-        super(context, attrs, defStyleAttr, defStyleRes);
-    }
-
-    @Override
-    public boolean onFilterTouchEventForSecurity(MotionEvent event) {
-        if ((event.getFlags() & MotionEvent.FLAG_WINDOW_IS_OBSCURED) != 0
-                || (event.getFlags() & MotionEvent.FLAG_WINDOW_IS_PARTIALLY_OBSCURED) != 0) {
-            // Window is obscured, drop this touch.
-            return false;
-        }
-        return true;
-    }
-}