Enable jumbo support for //components/omnibox

Without jumbo, omnibox takes around 3 CPU minutes to build
which is around 0.5 % of the total build time.

This commit enables jumbo support in components/omnibox.

Bug: 869381
Change-Id: Ifb51dab5a6b034a384c6bf07ee2f5b8c17b952a7
Reviewed-on: https://chromium-review.googlesource.com/1156593Reviewed-by: Tommy Li <tommycli@chromium.org>
Commit-Queue: Oscar Johansson <oscarj@opera.com>
Cr-Commit-Position: refs/heads/master@{#580114}

components/omnibox/browser/BUILD.gn

@@ -3,6 +3,7 @@
 # found in the LICENSE file.
 
 import("//build/buildflag_header.gni")
+import("//build/config/jumbo.gni")
 import("//device/vr/buildflags/buildflags.gni")
 import("//third_party/protobuf/proto_library.gni")
 import("//components/vector_icons/vector_icons.gni")
@@ -42,7 +43,7 @@ aggregate_vector_icons("omnibox_vector_icons") {
   ]
 }
 
-static_library("browser") {
+jumbo_static_library("browser") {
   sources = [
     "answers_cache.cc",
     "answers_cache.h",
@@ -227,7 +228,7 @@ proto_library("in_memory_url_index_cache_proto") {
   ]
 }
 
-static_library("test_support") {
+jumbo_static_library("test_support") {
   testonly = true
   sources = [
     "fake_autocomplete_provider_client.cc",