From 8a2656d4b69efcec5140f3de5a9a721ffb21112e Mon Sep 17 00:00:00 2001
From: Miranda Kephart <mkephart@google.com>
Date: Mon, 16 Nov 2020 11:22:13 -0500
Subject: [PATCH] [DO NOT MERGE] Close screenshot process on user switched

Currently, we keep the process up even if the user switches,
meaning that in some cases (if the user is switched while the
screenshot UI is up) we will save images to the wrong profile.
This change makes ScreenshotHelper listen for user switches and
close the screenshot service, so that a new screenshot is
guaranteed to be constructed with the correct user's context.

Bug: 170474245
Fix: 170474245
Test: manual -- verified bad state occurs if user switches within
the timeout period, ensured that screenshots work immediately
after switching with this change.

Change-Id: I9d32d0928e6c2bda161d04555438d0dd7afef0ba
(cherry picked from commit 7ef1a5dd1506075507412626f2533283d9520144)
---
 .../server/policy/PhoneWindowManager.java     | 25 ++++++++++++++-----
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/services/core/java/com/android/server/policy/PhoneWindowManager.java b/services/core/java/com/android/server/policy/PhoneWindowManager.java
index cd82d086d6efa..ada1ce3fa5dce 100644
--- a/services/core/java/com/android/server/policy/PhoneWindowManager.java
+++ b/services/core/java/com/android/server/policy/PhoneWindowManager.java
@@ -5837,8 +5837,7 @@ public class PhoneWindowManager implements WindowManagerPolicy {
         @Override public void run() {
             synchronized (mScreenshotLock) {
                 if (mScreenshotConnection != null) {
-                    mContext.unbindService(mScreenshotConnection);
-                    mScreenshotConnection = null;
+                    resetScreenshotConnection();
                     notifyScreenshotError();
                 }
             }
@@ -5870,8 +5869,7 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                             public void handleMessage(Message msg) {
                                 synchronized (mScreenshotLock) {
                                     if (mScreenshotConnection == myConn) {
-                                        mContext.unbindService(mScreenshotConnection);
-                                        mScreenshotConnection = null;
+                                        resetScreenshotConnection();
                                         mHandler.removeCallbacks(mScreenshotTimeout);
                                     }
                                 }
@@ -5894,8 +5892,7 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                 public void onServiceDisconnected(ComponentName name) {
                     synchronized (mScreenshotLock) {
                         if (mScreenshotConnection != null) {
-                            mContext.unbindService(mScreenshotConnection);
-                            mScreenshotConnection = null;
+                            resetScreenshotConnection();
                             mHandler.removeCallbacks(mScreenshotTimeout);
                             notifyScreenshotError();
                         }
@@ -5925,6 +5922,16 @@ public class PhoneWindowManager implements WindowManagerPolicy {
         mContext.sendBroadcastAsUser(errorIntent, UserHandle.CURRENT);
     }
 
+    /**
+     * Reset the screenshot connection.
+     */
+    private void resetScreenshotConnection() {
+        if (mScreenshotConnection != null) {
+            mContext.unbindService(mScreenshotConnection);
+            mScreenshotConnection = null;
+        }
+    }
+
     /** {@inheritDoc} */
     @Override
     public int interceptKeyBeforeQueueing(KeyEvent event, int policyFlags) {
@@ -6605,6 +6612,12 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                     mLastSystemUiFlags = 0;
                     updateSystemUiVisibilityLw();
                 }
+
+                // close the screenshot connection on user switch so that screenshots
+                // are always started with the correct user's context
+                synchronized(mScreenshotLock) {
+                  resetScreenshotConnection();
+                }
             }
         }
     };