* 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

No code changes, just comments: I spell-checked all the comments in the repo.

* implicit-casts:false on flutter_tools/lib

* address review comments

* use castStringKeyedMap

* introduce {bool,string,strings}Arg

* fix ci

This reverts commit 3597bae6.

When we were running `pub` within `flutter pub`, we were
unconditionally including the `--verbosity=warning` argument.
Then we were conditionally including `--verbose` if we were
running in verbose mode.  However, the former argument
supersedes the latter, and we were never able to run `pub`
in verbose mode.

* more ui-as-code

* address review comments

Substantially reduces the danger that a bug in the analysis server
might prevent errors from being detected by `flutter analyze`.

* add trailing commas on list/map/parameters

* add trailing commas on Invocation with nb of arg>1

* add commas for widget containing widgets

* add trailing commas if instantiation contains trailing comma

* revert bad change

These are essentially self-inflicted race conditions. Instead of timeouts we're going to try a more verbose logging mechanism that points out when things are taking a long time.

This reverts commit 76f70810.

* Remove many timeouts.

These are essentially self-inflicted race conditions. Instead of timeouts we're going to try a more verbose logging mechanism that points out when things are taking a long time.

* Get the attach tests to pass.

* Apply review comments from Todd

* More review comment fixes

* Put back the extended timeouts here now that I know why we have them...

This re-lands 3c56e6c7 on top of a new Dart SDK that contains new mixin syntax fixes.