WebUI: Auto-generate grd entries for ui/webui/resources/js, part 2

In preparation of moving all IDR_WEBUI_JS_* resources to
webui_generated_resources.grd, the new webui_generated_resources.pak
file needs to be included in fuchsia/engine/.

Bug: 1132403
Change-Id: I5c762bb01d30401866b266f9b9c374636e78ec69
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2521841
Auto-Submit: dpapad <dpapad@chromium.org>
Reviewed-by: Kevin Marshall <kmarshall@chromium.org>
Commit-Queue: Kevin Marshall <kmarshall@chromium.org>
Commit-Queue: dpapad <dpapad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#824584}

fuchsia/engine/BUILD.gn

@@ -226,7 +226,10 @@ executable("web_engine_exe") {
 }
 
 source_set("webui_resources") {
-  data = [ "$root_gen_dir/ui/resources/webui_resources.pak" ]
+  data = [
+    "$root_gen_dir/ui/resources/webui_generated_resources.pak",
+    "$root_gen_dir/ui/resources/webui_resources.pak",
+  ]
   deps = [ "//ui/resources" ]
 }
 

fuchsia/engine/web_engine_main_delegate.cc

@@ -28,6 +28,8 @@ WebEngineMainDelegate* g_current_web_engine_main_delegate = nullptr;
 void InitializeResources() {
   constexpr char kWebEnginePakPath[] = "web_engine.pak";
   constexpr char kWebUiResourcesPakPath[] = "ui/resources/webui_resources.pak";
+  constexpr char kWebUiGeneratedResourcesPakPath[] =
+      "ui/resources/webui_generated_resources.pak";
 
   base::FilePath asset_root;
   bool result = base::PathService::Get(base::DIR_ASSETS, &asset_root);
@@ -42,6 +44,13 @@ void InitializeResources() {
     ui::ResourceBundle::GetSharedInstance().AddDataPackFromPath(
         webui_resources_path, ui::SCALE_FACTOR_NONE);
   }
+
+  base::FilePath webui_generated_resources_path =
+      asset_root.Append(kWebUiGeneratedResourcesPakPath);
+  if (base::PathExists(webui_generated_resources_path)) {
+    ui::ResourceBundle::GetSharedInstance().AddDataPackFromPath(
+        webui_generated_resources_path, ui::SCALE_FACTOR_NONE);
+  }
 }
 
 }  // namespace