* Use Xcode build configurations to drive Flutter build mode
* Proper check wrt local_engine, print error if profile mode misisng
* Remove unused code, update tests, fix template problem, update warning
* fix up warning
* add explanatory dev comment
* fix whitespace
* missing words, change lambda arrow to function body
* error indentation
* Test early exits for xcode_backend.sh
* only on macOS, use right test
* Update error messages
* case insensitive compare for build config
* Update gallery podfile
* update projects to add profile configuration
* make compatible with flavors
* add missing plist files
We now use a different approach for ios projects where the developer controls
the Xcode project file. This patch removes the old ".generated" approach in
favor of the new approach.
