tst_QAccessibility fails on most of the platforms

tst_QAccessibility::textEditTest() fails on:

• linux-g++-32_Ubuntu_10.04_x86
• linux-g++_developer-build_qtnamespace_qtlibinfix_Ubuntu_11.10_x64

tst_QAccessibility::text() fails on:

• linux-g++-32_Ubuntu_10.04_x86
• linux-g++_developer-build_qtnamespace_qtlibinfix_Ubuntu_11.10_x64
• macx-g++_OSX_10.6
• macx-g++_OSX_10.7
• macx-g++_developer-build_OSX_10.7
• win32-msvc2010_Windows_7
• win32-msvc2010_developer-build_Windows_7

tst_QAccessibility::sliderTest() fails on:

• macx-g++_OSX_10.6
• macx-g++_OSX_10.7
• macx-g++_developer-build_OSX_10.7

tst_QAccessibility::comboBoxTest() fails on:

• linux-g++_developer-build_qtnamespace_qtlibinfix_Ubuntu_11.10_x64