Add more components_unittests to GN build

components/guest_view/browser/BUILD.gn

Index: components/guest_view/browser/BUILD.gn
diff --git a/components/guest_view/browser/BUILD.gn b/components/guest_view/browser/BUILD.gn
index d5885821f82b53cd682ed0471154e5023b301c1e..0aba6125617ecfb40cf9c00c68909b57ed9b229c 100644
--- a/components/guest_view/browser/BUILD.gn
+++ b/components/guest_view/browser/BUILD.gn
@@ -36,8 +36,19 @@ source_set("test_support") {
     "//components/guest_view/browser/test_guest_view_manager.h",
   ]
 
-  deps = [
+  public_deps = [
     ":browser",
     "//content/test:test_support",
   ]
 }
+
+source_set("unit_tests") {
+  testonly = true
+  sources = [
+    "guest_view_manager_unittest.cc",
+  ]
+  deps = [
+    ":test_support",
+    "//testing/gtest",
+  ]
+}