Split up ios/web:test_support.

ios/web/test/BUILD.gn

Index: ios/web/test/BUILD.gn
diff --git a/ios/web/test/BUILD.gn b/ios/web/test/BUILD.gn
index 5ddfc4db6dc4fdbdf4fb6fd7de53adb225af2953..4bd625d11ff4372ef9d1ccba5ad28b7d0d47648c 100644
--- a/ios/web/test/BUILD.gn
+++ b/ios/web/test/BUILD.gn
@@ -43,3 +43,33 @@ grit("resources") {
     "root_gen_dir=" + rebase_path(root_gen_dir, root_build_dir),
   ]
 }
+
+source_set("test_support") {
+  testonly = true
+
+  deps = [
+    "//base",
+    "//base/test:test_support",
+    "//ios/web:web",
+    "//testing/gtest",
+    "//third_party/ocmock",
+    "//ui/base",
+  ]
+
+  sources = [
+    "crw_fake_web_controller_observer.h",
+    "crw_fake_web_controller_observer.mm",
+    "test_url_constants.cc",
+    "test_url_constants.h",
+    "test_web_thread.cc",
+    "test_web_thread_bundle.cc",
+    "url_test_util.mm",
+    "web_int_test.h",
+    "web_int_test.mm",
+    "web_test_suite.mm",
+    "web_test_with_web_controller.h",
+    "web_test_with_web_controller.mm",
+    "wk_web_view_crash_utils.h",
+    "wk_web_view_crash_utils.mm",
+  ]
+}