[iOS][web] Change the WebView target to util

This CL changes the BUILDgn target in ios/web/web_view from web_view
to util, to reflect its current content.

Bug: none
Change-Id: I74eb4bb167b32bfc4dc4875abd6920e1d620ef9d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1625998Reviewed-by: Yi Su <mrsuyi@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#662613}

ios/web/navigation/BUILD.gn

@@ -27,7 +27,7 @@ source_set("navigation") {
     "//ios/web/web_state:user_interaction",
     "//ios/web/web_state:web_state_impl_header",
     "//ios/web/web_state/ui:crw_web_view_navigation_proxy",
-    "//ios/web/web_view",
+    "//ios/web/web_view:util",
     "//ui/base",
     "//url",
   ]

ios/web/web_state/ui/BUILD.gn

@@ -36,7 +36,7 @@ source_set("ui") {
     "//ios/web/web_state/js",
     "//ios/web/web_state/ui:wk_web_view_configuration_provider",
     "//ios/web/web_state/ui/controller",
-    "//ios/web/web_view",
+    "//ios/web/web_view:util",
     "//ios/web/webui:webui",
     "//services/metrics/public/cpp:ukm_builders",
     "//ui/base",

ios/web/web_view/BUILD.gn

@@ -4,7 +4,7 @@
 
 import("//ios/build/config.gni")
 
-source_set("web_view") {
+source_set("util") {
   sources = [
     "wk_web_view_util.h",
     "wk_web_view_util.mm",
@@ -21,7 +21,7 @@ source_set("unittests") {
   configs += [ "//build/config/compiler:enable_arc" ]
   testonly = true
   deps = [
-    ":web_view",
+    ":util",
     "//base",
     "//base/test:test_support",
     "//testing/gtest",