From ad6f2e580f783d5d320d3265bd617adedf55c944 Mon Sep 17 00:00:00 2001
From: Andrii Kulian <akulian@google.com>
Date: Wed, 15 Jun 2016 15:27:01 -0700
Subject: [PATCH] Bring task to front when we can't move to adjacent stack

If task was requested to move to adjacent stack with mLaunchStackId set
and FLAG_ACTIVITY_LAUNCH_ADJACENT not set - we don't move it from its
current stack. If the task was covered with other task(s) it wouldn't
be brought to front.
This CL checks if mLaunchStackId is provided and is a valid stack for this
task, then we move it to front of current stack as a safer option.

Bug: 29103549
Change-Id: I3065960f082cfbf9a5b43c6e83b5cebe3dd69df6
---
 .../android/server/am/ActivityStarter.java    | 25 +++++++++++++------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/services/core/java/com/android/server/am/ActivityStarter.java b/services/core/java/com/android/server/am/ActivityStarter.java
index 522e42bda94be..e42548488ebe8 100644
--- a/services/core/java/com/android/server/am/ActivityStarter.java
+++ b/services/core/java/com/android/server/am/ActivityStarter.java
@@ -1465,14 +1465,23 @@ class ActivityStarter {
                                 intentActivity.task, mNoAnimation, mOptions,
                                 mStartActivity.appTimeTracker, "bringingFoundTaskToFront");
                         mMovedToFront = true;
-                    } else if ((launchStack.mStackId == DOCKED_STACK_ID
-                            || launchStack.mStackId == FULLSCREEN_WORKSPACE_STACK_ID)
-                            && (mLaunchFlags & FLAG_ACTIVITY_LAUNCH_ADJACENT) != 0) {
-                        // If we want to launch adjacent and mTargetStack is not the computed
-                        // launch stack - move task to top of computed stack.
-                        mSupervisor.moveTaskToStackLocked(intentActivity.task.taskId,
-                                launchStack.mStackId, ON_TOP, FORCE_FOCUS, "launchToSide",
-                                ANIMATE);
+                    } else if (launchStack.mStackId == DOCKED_STACK_ID
+                            || launchStack.mStackId == FULLSCREEN_WORKSPACE_STACK_ID) {
+                        if ((mLaunchFlags & FLAG_ACTIVITY_LAUNCH_ADJACENT) != 0) {
+                            // If we want to launch adjacent and mTargetStack is not the computed
+                            // launch stack - move task to top of computed stack.
+                            mSupervisor.moveTaskToStackLocked(intentActivity.task.taskId,
+                                    launchStack.mStackId, ON_TOP, FORCE_FOCUS, "launchToSide",
+                                    ANIMATE);
+                        } else {
+                            // TODO: This should be reevaluated in MW v2.
+                            // We choose to move task to front instead of launching it adjacent
+                            // when specific stack was requested explicitly and it appeared to be
+                            // adjacent stack, but FLAG_ACTIVITY_LAUNCH_ADJACENT was not set.
+                            mTargetStack.moveTaskToFrontLocked(intentActivity.task, mNoAnimation,
+                                    mOptions, mStartActivity.appTimeTracker,
+                                    "bringToFrontInsteadOfAdjacentLaunch");
+                        }
                         mMovedToFront = true;
                     }
                     mOptions = null;