Set MaxInitialLineSize from maxInitialSizeKB config

MaxInitialLineSize parameter is not set from the config. This appears to
be a regression in 1.7.x

This commit adds test case to demonstrate the issue and a fix

Fixes linkerd#2393

Signed-off-by: Dmytro Kostiuchenko <edio@archlinux.us>

linkerd/protocol/http/src/main/scala/io/buoyant/linkerd/protocol/HttpConfig.scala

@@ -267,6 +267,7 @@ case class HttpConfig(
     .maybeWith(httpAccessLogAppend.map(AccessLogger.param.Append.apply))
     .maybeWith(httpAccessLogRotateCount.map(AccessLogger.param.RotateCount.apply))
     .maybeWith(maxHeadersKB.map(kb => hparam.MaxHeaderSize(kb.kilobytes)))
+    .maybeWith(maxInitialLineKB.map(kb => hparam.MaxInitialLineSize(kb.kilobytes)))
     .maybeWith(streamAfterContentLengthKB.map(kb => hparam.FixedLengthStreamedAfter(kb.kilobytes)))
     .maybeWith(Some(streaming))
     .maybeWith(Some(hparam.MaxRequestSize(MaxReqRespSize)))

linkerd/protocol/http/src/test/scala/io/buoyant/linkerd/protocol/http/HttpConfigTest.scala

@@ -2,9 +2,10 @@ package io.buoyant.linkerd.protocol.http
 
 import com.fasterxml.jackson.databind.exc.InvalidDefinitionException
 import com.twitter.finagle.buoyant.Dst
-import com.twitter.finagle.http.param.Streaming
+import com.twitter.finagle.http.param.{MaxInitialLineSize, Streaming}
 import com.twitter.finagle.http.{Method, Request}
 import com.twitter.finagle.{Dtab, Path, Stack}
+import com.twitter.conversions.StorageUnitOps._
 import com.twitter.util.Future
 import io.buoyant.config.Parser
 import io.buoyant.linkerd.protocol.{HttpConfig, HttpIdentifierConfig, HttpInitializer}
@@ -14,7 +15,6 @@ import io.buoyant.router.RoutingFactory.{IdentifiedRequest, Identifier}
 import io.buoyant.router.http.TimestampHeaderFilter
 import io.buoyant.test.{Awaits, FunSuite}
 
-
 class HttpConfigTest extends FunSuite with Awaits {
 
   def parse(yaml: String): HttpConfig = {
@@ -102,6 +102,21 @@ class HttpConfigTest extends FunSuite with Awaits {
     assert(streaming.enabled)
   }
 
+  test("Issue #2393 - MaxInitialLineSize set from config") {
+    val yaml = s"""
+                  |protocol: http
+                  |identifier:
+                  |  kind: io.l5d.methodAndHost
+                  |maxInitialLineKB: 64
+                  |servers:
+                  |- port: 5000
+      """.stripMargin
+    val config = parse(yaml)
+
+    val maxInitialLineKB = config.routerParams(Stack.Params.empty)[MaxInitialLineSize]
+    assert(maxInitialLineKB.size == 64.kilobytes)
+  }
+
   test("ConfigErrorTest - Stream disabled, streamAfter Set") {
     val yaml = s"""
                   |protocol: http