gofix -r mapdelete

R=golang-dev, r, adg, r, cw
CC=golang-dev
https://golang.org/cl/5266045
diff --git a/src/pkg/http/fcgi/child.go b/src/pkg/http/fcgi/child.go
index 1971882..61dd3fb 100644
--- a/src/pkg/http/fcgi/child.go
+++ b/src/pkg/http/fcgi/child.go
@@ -194,7 +194,7 @@
 		case typeData:
 			// If the filter role is implemented, read the data stream here.
 		case typeAbortRequest:
-			requests[rec.h.Id] = nil, false
+			delete(requests, rec.h.Id)
 			c.conn.writeEndRequest(rec.h.Id, 0, statusRequestComplete)
 			if !req.keepConn {
 				// connection will close upon return
diff --git a/src/pkg/http/persist.go b/src/pkg/http/persist.go
index 78bf905..f73e6c6 100644
--- a/src/pkg/http/persist.go
+++ b/src/pkg/http/persist.go
@@ -165,7 +165,7 @@
 	// Retrieve the pipeline ID of this request/response pair
 	sc.lk.Lock()
 	id, ok := sc.pipereq[req]
-	sc.pipereq[req] = 0, false
+	delete(sc.pipereq, req)
 	if !ok {
 		sc.lk.Unlock()
 		return ErrPipeline
@@ -353,7 +353,7 @@
 	// Retrieve the pipeline ID of this request/response pair
 	cc.lk.Lock()
 	id, ok := cc.pipereq[req]
-	cc.pipereq[req] = 0, false
+	delete(cc.pipereq, req)
 	if !ok {
 		cc.lk.Unlock()
 		return nil, ErrPipeline
diff --git a/src/pkg/http/transfer.go b/src/pkg/http/transfer.go
index 300c7a8..868a114 100644
--- a/src/pkg/http/transfer.go
+++ b/src/pkg/http/transfer.go
@@ -366,7 +366,7 @@
 		return nil, nil
 	}
 
-	header["Transfer-Encoding"] = nil, false
+	delete(header, "Transfer-Encoding")
 
 	// Head responses have no bodies, so the transfer encoding
 	// should be ignored.
@@ -399,7 +399,7 @@
 		// Chunked encoding trumps Content-Length. See RFC 2616
 		// Section 4.4. Currently len(te) > 0 implies chunked
 		// encoding.
-		header["Content-Length"] = nil, false
+		delete(header, "Content-Length")
 		return te, nil
 	}
 
diff --git a/src/pkg/http/transport.go b/src/pkg/http/transport.go
index b0aea97..0914af7 100644
--- a/src/pkg/http/transport.go
+++ b/src/pkg/http/transport.go
@@ -266,7 +266,7 @@
 		}
 		if len(pconns) == 1 {
 			pconn = pconns[0]
-			t.idleConn[key] = nil, false
+			delete(t.idleConn, key)
 		} else {
 			// 2 or more cached connections; pop last
 			// TODO: queue?