http2/hpack: remove pair function and initialize directly

Inlining isn't performed on generated init functions.  Removing the pair
function and initializing the structs directly saves another 16k on a
simple http.ListenAndServe() binary.

delta   name                                      old      new
-58     runtime.findfunctab                       10471    10413         -0.55%
-41     runtime.gcbss                             910      869           -4.51%
41      runtime.gcdata                            612      653            6.70%
-408    runtime.pclntab                           1036311  1035903       -0.04%
-11711  vendor/golang_org/x/net/http2/hpack.init  12283    572          -95.34%

Updates golang/go#6853

Change-Id: Ibccc796fe7403674cf4b4561acf9551d76ff11e8
Reviewed-on: https://go-review.googlesource.com/43190
Run-TryBot: Todd Neal <todd@tneal.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

http2/hpack/tables.go

diff --git a/http2/hpack/tables.go b/http2/hpack/tables.go
index 5d7f635..dd60ffd 100644
--- a/http2/hpack/tables.go
+++ b/http2/hpack/tables.go
@@ -132,67 +132,67 @@
 // http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-07#appendix-B
 var staticTable = newStaticTable()
 var staticTableEntries = [...]HeaderField{
-	pair(":authority", ""),
-	pair(":method", "GET"),
-	pair(":method", "POST"),
-	pair(":path", "/"),
-	pair(":path", "/index.html"),
-	pair(":scheme", "http"),
-	pair(":scheme", "https"),
-	pair(":status", "200"),
-	pair(":status", "204"),
-	pair(":status", "206"),
-	pair(":status", "304"),
-	pair(":status", "400"),
-	pair(":status", "404"),
-	pair(":status", "500"),
-	pair("accept-charset", ""),
-	pair("accept-encoding", "gzip, deflate"),
-	pair("accept-language", ""),
-	pair("accept-ranges", ""),
-	pair("accept", ""),
-	pair("access-control-allow-origin", ""),
-	pair("age", ""),
-	pair("allow", ""),
-	pair("authorization", ""),
-	pair("cache-control", ""),
-	pair("content-disposition", ""),
-	pair("content-encoding", ""),
-	pair("content-language", ""),
-	pair("content-length", ""),
-	pair("content-location", ""),
-	pair("content-range", ""),
-	pair("content-type", ""),
-	pair("cookie", ""),
-	pair("date", ""),
-	pair("etag", ""),
-	pair("expect", ""),
-	pair("expires", ""),
-	pair("from", ""),
-	pair("host", ""),
-	pair("if-match", ""),
-	pair("if-modified-since", ""),
-	pair("if-none-match", ""),
-	pair("if-range", ""),
-	pair("if-unmodified-since", ""),
-	pair("last-modified", ""),
-	pair("link", ""),
-	pair("location", ""),
-	pair("max-forwards", ""),
-	pair("proxy-authenticate", ""),
-	pair("proxy-authorization", ""),
-	pair("range", ""),
-	pair("referer", ""),
-	pair("refresh", ""),
-	pair("retry-after", ""),
-	pair("server", ""),
-	pair("set-cookie", ""),
-	pair("strict-transport-security", ""),
-	pair("transfer-encoding", ""),
-	pair("user-agent", ""),
-	pair("vary", ""),
-	pair("via", ""),
-	pair("www-authenticate", ""),
+	HeaderField{Name: ":authority"},
+	HeaderField{Name: ":method", Value: "GET"},
+	HeaderField{Name: ":method", Value: "POST"},
+	HeaderField{Name: ":path", Value: "/"},
+	HeaderField{Name: ":path", Value: "/index.html"},
+	HeaderField{Name: ":scheme", Value: "http"},
+	HeaderField{Name: ":scheme", Value: "https"},
+	HeaderField{Name: ":status", Value: "200"},
+	HeaderField{Name: ":status", Value: "204"},
+	HeaderField{Name: ":status", Value: "206"},
+	HeaderField{Name: ":status", Value: "304"},
+	HeaderField{Name: ":status", Value: "400"},
+	HeaderField{Name: ":status", Value: "404"},
+	HeaderField{Name: ":status", Value: "500"},
+	HeaderField{Name: "accept-charset"},
+	HeaderField{Name: "accept-encoding", Value: "gzip, deflate"},
+	HeaderField{Name: "accept-language"},
+	HeaderField{Name: "accept-ranges"},
+	HeaderField{Name: "accept"},
+	HeaderField{Name: "access-control-allow-origin"},
+	HeaderField{Name: "age"},
+	HeaderField{Name: "allow"},
+	HeaderField{Name: "authorization"},
+	HeaderField{Name: "cache-control"},
+	HeaderField{Name: "content-disposition"},
+	HeaderField{Name: "content-encoding"},
+	HeaderField{Name: "content-language"},
+	HeaderField{Name: "content-length"},
+	HeaderField{Name: "content-location"},
+	HeaderField{Name: "content-range"},
+	HeaderField{Name: "content-type"},
+	HeaderField{Name: "cookie"},
+	HeaderField{Name: "date"},
+	HeaderField{Name: "etag"},
+	HeaderField{Name: "expect"},
+	HeaderField{Name: "expires"},
+	HeaderField{Name: "from"},
+	HeaderField{Name: "host"},
+	HeaderField{Name: "if-match"},
+	HeaderField{Name: "if-modified-since"},
+	HeaderField{Name: "if-none-match"},
+	HeaderField{Name: "if-range"},
+	HeaderField{Name: "if-unmodified-since"},
+	HeaderField{Name: "last-modified"},
+	HeaderField{Name: "link"},
+	HeaderField{Name: "location"},
+	HeaderField{Name: "max-forwards"},
+	HeaderField{Name: "proxy-authenticate"},
+	HeaderField{Name: "proxy-authorization"},
+	HeaderField{Name: "range"},
+	HeaderField{Name: "referer"},
+	HeaderField{Name: "refresh"},
+	HeaderField{Name: "retry-after"},
+	HeaderField{Name: "server"},
+	HeaderField{Name: "set-cookie"},
+	HeaderField{Name: "strict-transport-security"},
+	HeaderField{Name: "transfer-encoding"},
+	HeaderField{Name: "user-agent"},
+	HeaderField{Name: "vary"},
+	HeaderField{Name: "via"},
+	HeaderField{Name: "www-authenticate"},
 }
 
 func newStaticTable() *headerFieldTable {