Dart: Adds mojom pub package.
Dart: Adds mojom pub package.

Creates generate.dart script that installs generated .mojom.dart files into
the mojom pub package.

Updates Sky's deploy_sdk.py script to put mojom.dart files in locations where
they can be consumed by the generate.dart script once the SDK is published and
obtained via "pub get".

This CL is adapted from a patch by zra@google.com; most of the work here is his.

R=iposva@google.com

Review URL: https://codereview.chromium.org/1106383006

krisgiesing/sky_engine,mpcomplete/engine,jamesr/sky_engine,jason-simmons/sky_engine,krisgiesing/sky_engine,aam/engine,jamesr/flutter_engine,xunmengfeng/engine,krisgiesing/sky_engine,jimsimon/sky_engine,cdotstout/sky_engine,tvolkert/engine,mikejurka/engine,jimsimon/sky_engine,devoncarew/engine,mpcomplete/engine,jason-simmons/flutter_engine,lyceel/engine,aam/engine,chinmaygarde/sky_engine,xunmengfeng/engine,qiankunshe/sky_engine,zhangxq5012/sky_engine,aam/engine,xunmengfeng/engine,mikejurka/engine,Hixie/sky_engine,lyceel/engine,zhangxq5012/sky_engine,zhangxq5012/sky_engine,jimsimon/sky_engine,takaaptech/sky_engine,zhangxq5012/sky_engine,mpcomplete/engine,jamesr/sky_engine,tvolkert/engine,devoncarew/sky_engine,krisgiesing/sky_engine,mikejurka/engine,TribeMedia/sky_engine,devoncarew/sky_engine,takaaptech/sky_engine,abarth/sky_engine,jamesr/flutter_engine,flutter/engine,axinging/sky_engine,mdakin/engine,mxia/engine,qiankunshe/sky_engine,Hixie/sky_engine,tvolkert/engine,jamesr/flutter_engine,axinging/sky_engine,Hixie/sky_engine,Hixie/sky_engine,flutter/engine,mpcomplete/flutter_engine,tvolkert/engine,rmacnak-google/engine,jamesr/sky_engine,qiankunshe/sky_engine,zhangxq5012/sky_engine,afandria/sky_engine,rmacnak-google/engine,jamesr/flutter_engine,flutter/engine,chinmaygarde/flutter_engine,cdotstout/sky_engine,rmacnak-google/engine,aam/engine,xunmengfeng/engine,chinmaygarde/flutter_engine,mxia/engine,chinmaygarde/sky_engine,mpcomplete/engine,jason-simmons/flutter_engine,devoncarew/sky_engine,afandria/sky_engine,mikejurka/engine,devoncarew/engine,takaaptech/sky_engine,devoncarew/engine,chinmaygarde/flutter_engine,afandria/sky_engine,cdotstout/sky_engine,krisgiesing/sky_engine,mpcomplete/flutter_engine,jamesr/flutter_engine,jason-simmons/sky_engine,TribeMedia/sky_engine,devoncarew/engine,mdakin/engine,tvolkert/engine,takaaptech/sky_engine,flutter/engine,jamesr/sky_engine,krisgiesing/sky_engine,chinmaygarde/flutter_engine,iansf/sky_engine,Hixie/sky_engine,afandria/sky_engine,iansf/sky_engine,mikejurka/engine,takaaptech/sky_engine,jamesr/flutter_engine,Hixie/sky_engine,takaaptech/sky_engine,jason-simmons/flutter_engine,rmacnak-google/engine,afandria/sky_engine,chinmaygarde/sky_engine,mdakin/engine,jason-simmons/sky_engine,chinmaygarde/flutter_engine,zhangxq5012/sky_engine,iansf/sky_engine,abarth/sky_engine,axinging/sky_engine,rmacnak-google/engine,jimsimon/sky_engine,iansf/sky_engine,mpcomplete/engine,mikejurka/engine,axinging/sky_engine,mikejurka/engine,jamesr/sky_engine,chinmaygarde/sky_engine,qiankunshe/sky_engine,lyceel/engine,flutter/engine,jason-simmons/sky_engine,mxia/engine,lyceel/engine,jimsimon/sky_engine,lyceel/engine,devoncarew/sky_engine,aam/engine,qiankunshe/sky_engine,takaaptech/sky_engine,mikejurka/engine,tvolkert/engine,jamesr/sky_engine,aam/engine,axinging/sky_engine,afandria/sky_engine,mxia/engine,jason-simmons/sky_engine,devoncarew/sky_engine,mdakin/engine,cdotstout/sky_engine,devoncarew/engine,jamesr/flutter_engine,jimsimon/sky_engine,mxia/engine,mpcomplete/engine,TribeMedia/sky_engine,iansf/sky_engine,zhangxq5012/sky_engine,xunmengfeng/engine,Hixie/sky_engine,jimsimon/sky_engine,devoncarew/sky_engine,devoncarew/engine,lyceel/engine,chinmaygarde/sky_engine,jamesr/flutter_engine,TribeMedia/sky_engine,axinging/sky_engine,mxia/engine,jason-simmons/flutter_engine,jason-simmons/flutter_engine,chinmaygarde/flutter_engine,iansf/sky_engine,rmacnak-google/engine,iansf/sky_engine,mpcomplete/flutter_engine,mdakin/engine,flutter/engine,abarth/sky_engine,TribeMedia/sky_engine,afandria/sky_engine,abarth/sky_engine,mdakin/engine,abarth/sky_engine,jimsimon/sky_engine,jamesr/sky_engine,mpcomplete/engine,cdotstout/sky_engine,mxia/engine,qiankunshe/sky_engine,axinging/sky_engine,jason-simmons/sky_engine,chinmaygarde/sky_engine,abarth/sky_engine,qiankunshe/sky_engine,TribeMedia/sky_engine,chinmaygarde/sky_engine,Hixie/sky_engine,abarth/sky_engine,zhangxq5012/sky_engine,mikejurka/engine,jason-simmons/flutter_engine,krisgiesing/sky_engine,iansf/sky_engine,takaaptech/sky_engine,mpcomplete/flutter_engine,mpcomplete/flutter_engine,mxia/engine,TribeMedia/sky_engine,cdotstout/sky_engine,flutter/engine,TribeMedia/sky_engine,takaaptech/sky_engine,cdotstout/sky_engine,devoncarew/engine,flutter/engine,tvolkert/engine,jamesr/flutter_engine,axinging/sky_engine,aam/engine,chinmaygarde/flutter_engine,devoncarew/sky_engine,zhangxq5012/sky_engine,mdakin/engine,lyceel/engine,mpcomplete/engine,aam/engine,TribeMedia/sky_engine,xunmengfeng/engine,jason-simmons/flutter_engine,jason-simmons/sky_engine,rmacnak-google/engine,jason-simmons/flutter_engine,jimsimon/sky_engine,afandria/sky_engine,mpcomplete/flutter_engine,mdakin/engine,qiankunshe/sky_engine,axinging/sky_engine,xunmengfeng/engine