fix: Fixed scrolling code lenses into view

[andrewnester]

Issue #, if available:

Description of changes:
Brought back from c9 branch

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[codecov]

Codecov Report

Merging #4717 (108d059) into master (bf2c7e2) will increase coverage by 0.05%.
The diff coverage is 87.50%.

@@            Coverage Diff             @@
##           master    #4717      +/-   ##
==========================================
+ Coverage   71.19%   71.24%   +0.05%     
==========================================
  Files         553      553              
  Lines       55598    55602       +4     
  Branches    10392    10393       +1     
==========================================
+ Hits        39584    39615      +31     
+ Misses      16014    15987      -27     

Flag	Coverage Δ
unittests	71.24% <87.50%> (+0.05%)	⬆️

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Impacted Files	Coverage Δ
lib/ace/ext/code_lens.js	91.60% <87.50%> (-0.48%)	⬇️
lib/ace/editor.js	81.61% <0.00%> (+1.97%)	⬆️

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