Add browser globals to known globals and prevent "typeof" side-effects

[lukastaegert]

This PR contains:

• bugfix
• feature
• refactor
• documentation
• other

Are tests included?

• yes (bugfixes and features will not be merged without tests)
• no

Breaking Changes?

• yes (breaking changes will not be merged unless absolutely necessary)
• no

List any relevant issue numbers:
Resolves #3115

Description

This will make sure that typeof globalVariable is not considered a side-effect. Note that typeof globalFunction() would still be a side-effect as it should be. Also, unfortunately Rollup is not yet capable of "remembering" the result of such a check, so in

let x;
if (typeof myGlobal !== undefined) {
  x = myGlobal; // This will still trigger a side-effect
} 

[codecov]

Codecov Report

Merging #3117 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #3117      +/-   ##
==========================================
+ Coverage   89.28%   89.28%   +<.01%     
==========================================
  Files         165      165              
  Lines        5731     5732       +1     
  Branches     1740     1741       +1     
==========================================
+ Hits         5117     5118       +1     
  Misses        380      380              
  Partials      234      234

Impacted Files	Coverage Δ
src/ast/nodes/UnaryExpression.ts	76.19% <100%> (+1.19%)	⬆️
src/ast/nodes/shared/knownGlobals.ts	100% <100%> (ø)	⬆️

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[Conduitry]

👍 This seems like a reasonable way of getting at the same end result for my case. Thank you!

[Conduitry]

Nit, but maybe stick this comment above /* OBJECT */ instead?