feat: enable builtin spellchecker (#20692)

* chore: add code required to use chromes spellchecker

* chore: fix linting

* chore: manifests needs buildflags now

* chore: add dictionarySuggestions to the context menu event when the spellchecker is active

* chore: enable by default for windows builds

* chore: add patch to remove incognito usage in the spellchecker

* chore: add dependencies on spellcheck common and flags

* chore: conditionally include spell check panel impl

* chore: fix deps for spellcheck feature flags

* chore: add patch for electron resources

* chore: add dependency on //components/language/core/browser

* chore: patches to make hunspell work on windows

* build: collect hunspell dictionaries into a zip file and publish

* chore: clean up patches

* chore: add docs and set spell checker url method

* chore: fix error handling

* chore: fix hash logic

* build: update hunspell filename generator

* fix: default spellchecker list to the current system locale if we can

* docs: document the language getter

* chore: patch IDS_ resources for linux builds

* feat: add spellcheck webpref flag to disable the builtin spellchecker

* chore: fix docs typo

* chore: clean up spellchecker impl as per feedback

* remove unneeded deps

appveyor.yml

@@ -91,6 +91,7 @@ build_script:
   - ninja -C out/Default electron:electron_dist_zip
   - ninja -C out/Default shell_browser_ui_unittests
   - ninja -C out/Default electron:electron_mksnapshot_zip
+  - ninja -C out/Default electron:hunspell_dictionaries_zip
   - ninja -C out/Default electron:electron_chromedriver_zip
   - ninja -C out/Default third_party/electron_node:headers
   - appveyor PushArtifact out/Default/dist.zip
@@ -100,6 +101,7 @@ build_script:
   - 7z a node_headers.zip out\Default\gen\node_headers
   - appveyor PushArtifact node_headers.zip
   - appveyor PushArtifact out/Default/mksnapshot.zip
+  - appveyor PushArtifact out/Default/hunspell_dictionaries.zip
   - appveyor PushArtifact out/Default/electron.lib
   - ps: >-
       if ($env:GN_CONFIG -eq 'release') {