Skip QThread stress test on Qemu

Qemu uses some memory for each generated thread. This test creates
> 80000 threads and consumes about 10Gb of memory which is too
heavy for a VM.

Task-number: QTBUG-59966
Change-Id: I1bb8a0d7955778f5201948b41befcb9f1f391514
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

tests/auto/corelib/thread/qthread/qthread.pro

@@ -2,3 +2,6 @@ CONFIG += testcase
 TARGET = tst_qthread
 QT = core testlib
 SOURCES = tst_qthread.cpp
+
+INCLUDEPATH += ../../../../shared/
+HEADERS += ../../../../shared/emulationdetector.h

tests/auto/corelib/thread/qthread/tst_qthread.cpp

@@ -47,6 +47,8 @@
 #endif
 #endif
 
+#include "emulationdetector.h"
+
 class tst_QThread : public QObject
 {
     Q_OBJECT
@@ -937,6 +939,9 @@ void tst_QThread::adoptMultipleThreadsOverlap()
 // Disconnects on WinCE
 void tst_QThread::stressTest()
 {
+    if (EmulationDetector::isRunningArmOnX86())
+        QSKIP("Qemu uses too much memory for each thread. Test would run out of memory.");
+
     QTime t;
     t.start();
     while (t.elapsed() < one_minute) {