Make thread names more descriptive. (#5196)
Make thread names more descriptive. (#5196)

The thread on which the runner services `CreateApplication` calls is now called `io.flutter.runner.<aot|jit>`. Each application will launch four threads named `<application_name>.<platform|ui|io|gpu>`.

`fx shell ps -T` is an easy way to tell which runners are hosting which applications.
jason-simmons/flutter_engine,krisgiesing/sky_engine,chinmaygarde/sky_engine,devoncarew/engine,rmacnak-google/engine,Hixie/sky_engine,flutter/engine,tvolkert/engine,tvolkert/engine,mikejurka/engine,jason-simmons/sky_engine,mikejurka/engine,jamesr/sky_engine,cdotstout/sky_engine,jason-simmons/sky_engine,Hixie/sky_engine,jamesr/sky_engine,chinmaygarde/sky_engine,mikejurka/engine,devoncarew/sky_engine,flutter/engine,jamesr/flutter_engine,devoncarew/sky_engine,mikejurka/engine,mikejurka/engine,flutter/engine,jason-simmons/sky_engine,jason-simmons/flutter_engine,cdotstout/sky_engine,jamesr/flutter_engine,chinmaygarde/flutter_engine,chinmaygarde/sky_engine,jason-simmons/flutter_engine,rmacnak-google/engine,krisgiesing/sky_engine,Hixie/sky_engine,devoncarew/sky_engine,jason-simmons/flutter_engine,tvolkert/engine,chinmaygarde/flutter_engine,Hixie/sky_engine,aam/engine,jamesr/flutter_engine,krisgiesing/sky_engine,krisgiesing/sky_engine,jamesr/sky_engine,rmacnak-google/engine,rmacnak-google/engine,rmacnak-google/engine,chinmaygarde/flutter_engine,devoncarew/engine,chinmaygarde/sky_engine,devoncarew/engine,mikejurka/engine,devoncarew/sky_engine,jason-simmons/sky_engine,jason-simmons/sky_engine,krisgiesing/sky_engine,aam/engine,tvolkert/engine,jamesr/flutter_engine,devoncarew/sky_engine,mikejurka/engine,mikejurka/engine,devoncarew/sky_engine,Hixie/sky_engine,chinmaygarde/sky_engine,jamesr/sky_engine,jason-simmons/flutter_engine,jamesr/sky_engine,jason-simmons/flutter_engine,cdotstout/sky_engine,flutter/engine,tvolkert/engine,tvolkert/engine,jason-simmons/flutter_engine,flutter/engine,devoncarew/sky_engine,jamesr/flutter_engine,jamesr/flutter_engine,cdotstout/sky_engine,devoncarew/engine,cdotstout/sky_engine,aam/engine,devoncarew/engine,jamesr/sky_engine,cdotstout/sky_engine,jason-simmons/sky_engine,mikejurka/engine,flutter/engine,cdotstout/sky_engine,flutter/engine,jason-simmons/sky_engine,jamesr/flutter_engine,aam/engine,Hixie/sky_engine,krisgiesing/sky_engine,flutter/engine,jamesr/flutter_engine,aam/engine,rmacnak-google/engine,krisgiesing/sky_engine,chinmaygarde/flutter_engine,aam/engine,aam/engine,aam/engine,devoncarew/engine,chinmaygarde/sky_engine,Hixie/sky_engine,tvolkert/engine,jamesr/flutter_engine,jamesr/sky_engine,chinmaygarde/flutter_engine,chinmaygarde/flutter_engine,jason-simmons/flutter_engine,devoncarew/engine,rmacnak-google/engine,Hixie/sky_engine,chinmaygarde/flutter_engine,chinmaygarde/sky_engine