We need a UI for printer selection and the subset of print settings we want to support for v80. The initial patch should just rough in the main components and implement enough of a framework to unblock implementation of each feature and polish of the user experience.

We met to discuss which features we could implement without any backend support and came up with this list:

• Destination
• Orientation
• Copies
• Page range
  • Only a single range, validation to be done in bug 1653389
• More options
  • Zoom
  • Background images/colours
• Open native dialog
• Print silently
• Cancel
  • Just close the tab for now

Backed out 2 changesets (bug 1652861) for browser_all_files_referenced.js failures

Push with failures: https://treeherder.mozilla.org/#/jobs?repo=autoland&group_state=expanded&searchStr=os%2Cx%2C10.14%2Cshippable%2Copt%2Cmochitests%2Ctest-macosx1014-64-shippable%2Fopt-mochitest-browser-chrome-e10s%2Cbc5&fromchange=f5bfa5ea6f045557603e3029d8f79112dda201e6&tochange=bad2c20d6a8cbc9a0ad4ef15a7a50cdcc005a863&selectedTaskRun=SCAtH7gITwmRfJo2CiUUKQ.0

Backout link: https://hg.mozilla.org/integration/autoland/rev/bad2c20d6a8cbc9a0ad4ef15a7a50cdcc005a863

Failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=310492890&repo=autoland&lineNumber=1315

[task 2020-07-21T01:23:45.200Z] 01:23:45     INFO - TEST-START | browser/base/content/test/static/browser_all_files_referenced.js
[task 2020-07-21T01:23:51.113Z] 01:23:51     INFO - TEST-INFO | started process screencapture
[task 2020-07-21T01:23:51.236Z] 01:23:51     INFO - TEST-INFO | screencapture: exit 0
[task 2020-07-21T01:23:51.237Z] 01:23:51     INFO - Buffered messages logged at 01:23:45
[task 2020-07-21T01:23:51.238Z] 01:23:51     INFO - Entering test bound checkAllTheFiles
[task 2020-07-21T01:23:51.238Z] 01:23:51     INFO - Buffered messages logged at 01:23:51
[task 2020-07-21T01:23:51.238Z] 01:23:51     INFO - indirectly whitelisted file: chrome://marionette/content/test_dialog.dtd used from chrome://marionette/content/test_dialog.xhtml
...
[task 2020-07-21T01:23:51.249Z] 01:23:51     INFO - indirectly whitelisted file: chrome://fxr/content/prefs.js used from chrome://fxr/content/prefs.html
[task 2020-07-21T01:23:51.249Z] 01:23:51     INFO - TEST-PASS | browser/base/content/test/static/browser_all_files_referenced.js | there should be no unreferenced files - 
[task 2020-07-21T01:23:51.249Z] 01:23:51     INFO - Buffered messages finished
[task 2020-07-21T01:23:51.249Z] 01:23:51     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/static/browser_all_files_referenced.js | unused whitelist entry: resource://gre/localization/en-US/toolkit/printing/printDialogs.ftl - 
[task 2020-07-21T01:23:51.249Z] 01:23:51     INFO - Stack trace:
[task 2020-07-21T01:23:51.249Z] 01:23:51     INFO - chrome://mochikit/content/browser-test.js:test_ok:1299
[task 2020-07-21T01:23:51.250Z] 01:23:51     INFO - chrome://mochitests/content/browser/browser/base/content/test/static/browser_all_files_referenced.js:checkAllTheFiles:969
[task 2020-07-21T01:23:51.250Z] 01:23:51     INFO - ignored unused whitelist entry: resource://app/blocklist.xml
[task 2020-07-21T01:23:51.250Z] 01:23:51     INFO - ignored unused whitelist entry: resource://gre/gmp-clearkey/0.1/manifest.json
[task 2020-07-21T01:23:51.250Z] 01:23:51     INFO - ignored unused whitelist entry: resource://gre/res/test.properties
[task 2020-07-21T01:23:51.250Z] 01:23:51     INFO - missing file: resource://gre/components/nsAsyncShutdown.js
...
[task 2020-07-21T01:23:51.451Z] 01:23:51     INFO - missing file: resource://report-site-issue/tabExtrasActor.jsm referenced from jar:file:///Users/cltbld/tasks/task_1595294159/build/application/Firefox%20Nightly.app/Contents/Resources/browser/features/webcompat-reporter@mozilla.org.xpi!/experimentalAPIs/tabExtras.js
[task 2020-07-21T01:23:51.503Z] 01:23:51     INFO - Leaving test bound checkAllTheFiles
[task 2020-07-21T01:23:51.503Z] 01:23:51     INFO - Console message: No chrome package registered for chrome://geckoview/content/geckoview.xhtml
[task 2020-07-21T01:23:51.504Z] 01:23:51     INFO - Console message: No chrome package registered for chrome://gfxsanity/content/sanityparent.html
[task 2020-07-21T01:23:51.504Z] 01:23:51     INFO - Console message: No chrome package registered for chrome://help/content/help.js
[task 2020-07-21T01:23:51.507Z] 01:23:51     INFO - GECKO(1230) | MEMORY STAT vsizeMaxContiguous not supported in this build configuration.
[task 2020-07-21T01:23:51.510Z] 01:23:51     INFO - GECKO(1230) | MEMORY STAT | vsize 7773MB | residentFast 810MB | heapAllocated 568MB
[task 2020-07-21T01:23:51.510Z] 01:23:51     INFO - TEST-OK | browser/base/content/test/static/browser_all_files_referenced.js | took 6322ms
[task 2020-07-21T01:23:51.549Z] 01:23:51     INFO - checking window state
[task 2020-07-21T01:23:51.549Z] 01:23:51     INFO - TEST-START | browser/base/content/test/static/browser_misused_characters_in_strings.js
[task 2020-07-21T01:23:53.086Z] 01:23:53     INFO - GECKO(1230) | MEMORY STAT | vsize 8147MB | residentFast 913MB | heapAllocated 660MB
[task 2020-07-21T01:23:53.086Z] 01:23:53     INFO - TEST-OK | browser/base/content/test/static/browser_misused_characters_in_strings.js | took 1463ms
[task 2020-07-21T01:23:53.087Z] 01:23:53     INFO - checking window state
[task 2020-07-21T01:23:53.092Z] 01:23:53     INFO - TEST-START | browser/base/content/test/static/browser_parsable_css.js
[task 2020-07-21T01:23:54.158Z] 01:23:54     INFO - GECKO(1230) | MEMORY STAT | vsize 8174MB | residentFast 939MB | heapAllocated 688MB
[task 2020-07-21T01:23:54.158Z] 01:23:54     INFO - TEST-OK | browser/base/content/test/static/browser_parsable_css.js | took 1006ms
[task 2020-07-21T01:23:54.159Z] 01:23:54     INFO - checking window state
[task 2020-07-21T01:23:54.172Z] 01:23:54     INFO - TEST-START | browser/base/content/test/static/browser_parsable_script.js
[task 2020-07-21T01:24:07.775Z] 01:24:07     INFO - GECKO(1230) | MEMORY STAT | vsize 8348MB | residentFast 1021MB | heapAllocated 497MB
[task 2020-07-21T01:24:07.775Z] 01:24:07     INFO - TEST-OK | browser/base/content/test/static/browser_parsable_script.js | took 13596ms

Thanks. printDialogs.ftl is whitelisted as an un-referenced file in macosx builds. I had a new reference to it from the new print.html in anticipation of needing to use those strings in future patches. They are not currently used, so I've removed it for now.

As we build out the rest of the UI we may need some of these strings - or very similar strings - but as we're using html rather than xul (most strings in printDialogs.ftl are .label properties), I'm not sure if we'll be able to use them directly. We'll have both UIs for a little while so they can't just be directly migrated. Making that plan probably merits its own bug. I'll discuss with the team.

https://hg.mozilla.org/mozilla-central/rev/fb91e28a21b0
https://hg.mozilla.org/mozilla-central/rev/06ad38b3eaff