[check] IDE: Show/Show in Buttons should be revised

[RaiMan]

When I press the Show or Show in buttons I get a dialogue box saying 'Nothing to show'

If I press Show in then it asks me to draw a region. If the image
appears within that region, it highlights it. If it doesn't it will eg
stop with:

[error] Runner: not possible: CvException [org.opencv.core.CvException:
cv::Exception: OpenCV(3.4.2) C:\build\3_4_winpack-bindings-
win64-vc14-static\opencv\modules\imgproc\src\templmatch.cpp:1107: error:
(-215:Assertion failed) _img.size().height <= _templ.size().height &&
_img.size().width <= _templ.size().width in function 'cv::matchTemplate'
]
(Note testing these features has also given me 'null' or caused the IDE to crash.)