[Android] Do not ask for access permission at very beginning

src/dialogs/tlevelcreatoritem.cpp

src/dialogs/tlevelselector.cpp

src/libs/core/Android/tandroid.cpp

src/libs/core/Android/tandroid.h

src/libs/core/Android/tfiledialog.cpp

src/libs/core/exam/texam.cpp

src/libs/core/tglobals.cpp

src/libs/core/tnootkaqml.cpp

src/main.cpp

src/main/texamexecutor.cpp

src/main/tstartexamitem.cpp