Fix collapse tool when dragging from right to left

[astrofrog]

Still needs tests and need to make fixed_resolution_buffer function more robust to this kind of issue

[codecov]

Codecov Report

Merging #2002 into master will decrease coverage by 0.06%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #2002      +/-   ##
==========================================
- Coverage   87.76%   87.69%   -0.07%     
==========================================
  Files         248      248              
  Lines       21712    21713       +1     
==========================================
- Hits        19055    19042      -13     
- Misses       2657     2671      +14

Impacted Files	Coverage Δ
glue/viewers/image/state.py	90.09% <ø> (ø)	⬆️
glue/viewers/profile/qt/profile_tools.py	90.08% <100%> (+0.04%)	⬆️
glue/version.py	71.42% <0%> (-28.58%)	⬇️
glue/utils/qt/app.py	86.95% <0%> (-8.7%)	⬇️
glue/__init__.py	69.56% <0%> (-4.35%)	⬇️
glue/conftest.py	66% <0%> (-4%)	⬇️
glue/app/qt/preferences.py	92.3% <0%> (-2.57%)	⬇️
glue/viewers/matplotlib/qt/widget.py	77.52% <0%> (-1.13%)	⬇️
glue/core/data_factories/fits.py	87.59% <0%> (-0.73%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 48181a7...2d982ff. Read the comment docs.