Replace SpdyNameValueBlock typedef with SpdyHeaderBlock.
Replace SpdyNameValueBlock typedef with SpdyHeaderBlock. Use SpdyHeaderBlock typedef more widely. No behavior change intended.
This CL is preparation for replacing SpdyHeaderBlock with an ordered datatype. Using the typedef in every place that currently explicitly uses map<string,string> will make this easier.
Other cleanup: replacing NameValueBlock with HeaderBlock, as in every case this is being used to store headers.
This CL lands server change
98865397 by rjshade.
BUG=443287
Review URL: https://codereview.chromium.org/
1263803002
Cr-Commit-Position: refs/heads/master@{#341101}