42966 expand scope of rethrown gradle errors (cla: yes, tool)

42967 Pad CupertinoAlertDialog with MediaQuery viewInsets (cla: yes, f: cupertino, framework)

42968 Quick fix on material dialog docs (cla: yes, f: material design, framework)

42970 Rename headless server to web server (cla: yes, tool)

42971 re-enable some linux devicelab tests (cla: yes, team)

42972 Do not produce an error when encountering a new type in a service response. (cla: yes, tool)

42977 switch dart2js build to depfile, remove Source.function (cla: yes, tool)

42981 Remove GeneratedPluginRegistrant.java (cla: yes, team)