* 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
It's not just $HOME/.AndroidStudio2.2, it might also be
.AndroidStudioPreview2.3, or .AndroidStudioFooBar1.7, or whatever.
Made the Version parser less throw-happy, and relaxed the directory name
checks to allow for the above.
Fixes#8353.
* Fix bug parsing Gradle version.
Version from pub_semver requires versions of the format X.Y.Z. Gradle
doesn't follow semantic versioning, though, so version parsing would
fail on versions like '3.2'. Fixed by writing a custom Version class.
Also removed a check for apksigner when building Gradle-based projects.
Fixes#8298
