[flutter_tools] fix coverage measurement to report on lib and not test (#52093)
[flutter_tools] fix coverage measurement to report on lib and not test (#52093)


cbracken/flutter,Hixie/flutter,Hixie/flutter,cbracken/flutter,Hixie/flutter,flutter/flutter,tvolkert/flutter,Hixie/flutter,flutter/flutter,Hixie/flutter,cbracken/flutter,cbracken/flutter,cbracken/flutter,tvolkert/flutter,tvolkert/flutter,flutter/flutter,tvolkert/flutter,cbracken/flutter,tvolkert/flutter,cbracken/flutter,Hixie/flutter,Hixie/flutter,tvolkert/flutter,flutter/flutter,Hixie/flutter,flutter/flutter,cbracken/flutter,cbracken/flutter,flutter/flutter,tvolkert/flutter,flutter/flutter,flutter/flutter,flutter/flutter,tvolkert/flutter,tvolkert/flutter,tvolkert/flutter,Hixie/flutter,Hixie/flutter,cbracken/flutter,flutter/flutter