* Update project.pbxproj files to say Flutter rather than Chromium
Also, the templates now have an empty organization so that we don't cause people to give their apps a Flutter copyright.
* Update the copyright notice checker to require a standard notice on all files
* Update copyrights on Dart files. (This was a mechanical commit.)
* Fix weird license headers on Dart files that deviate from our conventions; relicense Shrine.
Some were already marked "The Flutter Authors", not clear why. Their
dates have been normalized. Some were missing the blank line after the
license. Some were randomly different in trivial ways for no apparent
reason (e.g. missing the trailing period).
* Clean up the copyrights in non-Dart files. (Manual edits.)
Also, make sure templates don't have copyrights.
* Fix some more ORGANIZATIONNAMEs
Improve Swift usage in platform_channel_swift some more
Make a bunch of changes that willlarche requested in
https://github.com/flutter/flutter/pull/21712:
* Use `static let` within `enum` namespaces for String constants.
* Use `guard` for early exits and to avoid forced unwrapping.
* Explicitly qualify a selector.
* Fix a retain cycle by using a weak reference.
Make platform_channels_swift use more idiomatic Swift
* Remove semicolons.
* `if (condition)` => `if condition`.
* `Class.init(...)` => `Class(...)`.
* Remove `break` statements from `switch` cases.
* Remove some unnecessary uses of `self`.
* wip
* wip
* delete main.m
* readd main.m
* update to use new channel api
* update android
* removed android/
* remove debug print
* remomved main.m
* Update year in copyright
* break long line and update name
* mit comments
* update examples/README
* break line
* update README
* update test
