[WebLayer] Add resources needed to load chrome://weblayer to webview APK

The chrome://weblayer page was not loading. This adds the necessary
resources to webview/monochrome.

Bug: 1017924
Change-Id: Iaa3831afa9408c271720e378f5893b8b0d019a97
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1880171Reviewed-by: Richard Coles <torne@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Commit-Queue: Clark DuVall <cduvall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#709538}

android_webview/BUILD.gn

@@ -146,17 +146,21 @@ repack("repack_pack") {
     "$root_gen_dir/content/content_resources.pak",
     "$root_gen_dir/net/net_resources.pak",
     "$root_gen_dir/third_party/blink/public/resources/blink_resources.pak",
+    "$root_gen_dir/weblayer/weblayer_resources.pak",
     "$target_gen_dir/aw_resources.pak",
     "$target_gen_dir/components_resources.pak",
+    "$target_gen_dir/mojo_bindings_resources.pak",
     "$target_gen_dir/webui_resources.pak",
   ]
   deps = [
     ":generate_aw_resources",
     ":generate_components_resources",
+    ":generate_mojo_resources",
     ":generate_webui_resources",
     "//content:resources",
     "//net:net_resources",
     "//third_party/blink/public:resources",
+    "//weblayer:resources",
   ]
   output = "$target_gen_dir/resources.pak"
 
@@ -271,6 +275,34 @@ grit("generate_webui_resources") {
   ]
 }
 
+grit("generate_mojo_resources") {
+  source = "../mojo/public/js/mojo_bindings_resources.grd"
+
+  # The .grd contains references to generated files.
+  source_is_generated = true
+
+  # See :generate_webui_resources for an explanation of the whitelist
+  _whitelist = "ui/grit_resources_whitelist.txt"
+  inputs = [
+    _whitelist,
+  ]
+  grit_flags = [
+    "-w",
+    rebase_path(_whitelist, root_build_dir),
+    "-E",
+    "root_gen_dir=" + rebase_path(root_gen_dir, root_build_dir),
+  ]
+  outputs = [
+    "grit/mojo_bindings_resources.h",
+    "grit/mojo_bindings_resources_map.cc",
+    "grit/mojo_bindings_resources_map.h",
+    "mojo_bindings_resources.pak",
+  ]
+  deps = [
+    "//mojo/public/js:bindings_lite",
+  ]
+}
+
 grit("generate_components_resources") {
   source = "../components/resources/components_resources.grd"
 

android_webview/ui/grit_resources_whitelist.txt

@@ -7,3 +7,7 @@ IDR_SECURITY_INTERSTITIAL_QUIET_HTML
 IDR_SAFE_BROWSING_CSS
 IDR_SAFE_BROWSING_JS
 IDR_SAFE_BROWSING_HTML
+IDR_WEBUI_JS_CR
+IDR_WEBUI_JS_UTIL
+IDR_WEBUI_JS_PROMISE_RESOLVER
+IDR_MOJO_MOJO_BINDINGS_LITE_JS

chrome/android/BUILD.gn

@@ -1384,9 +1384,14 @@ if (current_toolchain == default_toolchain) {
 
       additional_extra_paks = []
       if (_is_monochrome) {
-        additional_extra_paks +=
-            [ "$root_gen_dir/android_webview/aw_resources.pak" ]
-        deps += [ "//android_webview:generate_aw_resources" ]
+        additional_extra_paks += [
+          "$root_gen_dir/android_webview/aw_resources.pak",
+          "$root_gen_dir/weblayer/weblayer_resources.pak",
+        ]
+        deps += [
+          "//android_webview:generate_aw_resources",
+          "//weblayer:resources",
+        ]
       }
       if (!dfmify_dev_ui) {
         additional_extra_paks +=