net/QUIC: inline gypi file into BUILD.gn file and upstream proto-quic.
This is a redo of https://codereview.chromium.org/2475673004/
It is based of current net.gypi, and adds (suprisingly little?)
proto-quic specific logic to net/BUILD.gn. That is guarded by a new gn
build argument "is_proto_quic".
On the proto-quic side of things, this will deprecate the merge_net_* part of the update.py script entirely. Instead, this version of BUILD.gn should be directly usable there, with the caveat that gn be invoked as follows during the proto-quic merge:
gn --args="is_proto_quic=true" gen out/Default
I will update the instructions there in a followup cl (in proto-quic
github), as well as nuking most if not all of modified_files/.
It is also worth pointing out that this abandons the previous proto-quic
strategy of blacklisting new files under net/ by default. I think that
only added maintenance complexity and did not significantly reduce
proto-quic size or build times.
I have tested this under proto-quic, but plan to do a new merge to
double check, once this has landed.