AndroidDeviceManager: Remove the instance from plugin destructor

Delete the AndroidDeviceManager instance on shutdown from inside
android plugin destructor.

Implement AndroidDeviceManager destructor and wait for
futures currently running to finish. Don't do any special
handling for possibly still running m_adbDeviceWatcherProcess,
as it will be deleted automatically by the std::unique_ptr
and this will automatically initiate a proper termination of the
process running.

Change-Id: I5aad6f4fcfca23a0a37c3709efcdffad43a88203
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Assam Boudjelthia <assam.boudjelthia@qt.io>

src/plugins/android/androiddevice.cpp

@@ -836,10 +836,11 @@ void AndroidDeviceManager::HandleDevicesListChange(const QString &serialNumber)
     }
 }
 
+static AndroidDeviceManager *s_instance = nullptr;
+
 AndroidDeviceManager *AndroidDeviceManager::instance()
 {
-    static AndroidDeviceManager obj;
-    return &obj;
+    return s_instance;
 }
 
 AndroidDeviceManager::AndroidDeviceManager(QObject *parent)
@@ -847,18 +848,18 @@ AndroidDeviceManager::AndroidDeviceManager(QObject *parent)
       m_androidConfig(AndroidConfigurations::currentConfig()),
       m_avdManager(m_androidConfig)
 {
-    connect(qApp, &QCoreApplication::aboutToQuit, this, [this]() {
-        if (m_adbDeviceWatcherProcess) {
-            m_adbDeviceWatcherProcess->terminate();
-            m_adbDeviceWatcherProcess->waitForFinished();
-            m_adbDeviceWatcherProcess.reset();
-        }
-        m_avdsFutureWatcher.waitForFinished();
-        m_removeAvdFutureWatcher.waitForFinished();
-    });
-
     connect(&m_removeAvdFutureWatcher, &QFutureWatcherBase::finished,
             this, &AndroidDeviceManager::handleAvdRemoved);
+    QTC_ASSERT(!s_instance, return);
+    s_instance = this;
+}
+
+AndroidDeviceManager::~AndroidDeviceManager()
+{
+    m_avdsFutureWatcher.waitForFinished();
+    m_removeAvdFutureWatcher.waitForFinished();
+    QTC_ASSERT(s_instance == this, return);
+    s_instance = nullptr;
 }
 
 // Factory

src/plugins/android/androiddevice.h

@@ -123,6 +123,7 @@ public:
 
 private:
     AndroidDeviceManager(QObject *parent = nullptr);
+    ~AndroidDeviceManager();
     void HandleDevicesListChange(const QString &serialNumber);
     void HandleAvdsListChange();
     void handleAvdRemoved();
@@ -135,6 +136,8 @@ private:
     std::unique_ptr<Utils::QtcProcess> m_adbDeviceWatcherProcess;
     AndroidConfig &m_androidConfig;
     AndroidAvdManager m_avdManager;
+
+    friend class AndroidPluginPrivate;
 };
 
 } // namespace Internal

src/plugins/android/androidplugin.cpp

@@ -136,6 +136,7 @@ public:
     };
 
     AndroidBuildApkStepFactory buildApkStepFactory;
+    AndroidDeviceManager deviceManager;
 };
 
 AndroidPlugin::~AndroidPlugin()