Use strict equalities in web/ui_utils.js
Use strict equalities in web/viewer.js
Use strict equalities in web/document_properties.js
Add strict equalities in src/shared/fonts_utils.js
Add strict equalities in src/shared/util.js
Use strict equalities in web/debugger.js
Use strict equalities in web/compatibility.js
Merge pull request #5108 from timvandermeij/strict-equalities

Use strict equalities in web/*
Merge pull request #5112 from Snuffleupagus/strict-equalities-src-shared

Add strict equalities in src/shared/*