[WebView] Move WebLayer's resource exclusions into //weblayer

This CL follows up the addition of WebLayer-specific resource
exclusions in
https://chromium-review.googlesource.com/c/chromium/src/+/2209678 and
https://chromium-review.googlesource.com/c/chromium/src/+/2250109. When
introduced, all of the GN goop for these exclusions was placed directly
in system_webview_apk_tmpl.gni. This CL addresses Bo's request from the
latter CL above to introduce proper layering so that the
//android_webview file doesn't have to directly worry about what
WebLayer's exclusions are.

I verified manually with run_weblayer_shell_trichrome that the
translate infobar and HTTP auth dialog both still show as expected with
this change.

Bug: 1093846
Change-Id: Id354c07073ec031002a1e0089fe531c5ab7ecfc5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2257321Reviewed-by: Bo <boliu@chromium.org>
Commit-Queue: Colin Blundell <blundell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#780764}

android_webview/system_webview_apk_tmpl.gni

@@ -11,6 +11,7 @@ import("//build/util/version.gni")
 import("//chrome/android/trichrome.gni")
 import("//tools/v8_context_snapshot/v8_context_snapshot.gni")
 import("//weblayer/variables.gni")
+import("//weblayer/weblayer_resource_exclusions.gni")
 
 declare_args() {
   # Android package name to use when compiling the system_webview_apk and
@@ -181,61 +182,14 @@ template("system_webview_apk_or_module_tmpl") {
     resource_exclusion_regex = common_resource_exclusion_regex
     resource_exclusion_exceptions = common_resource_exclusion_exceptions
 
-    _material_package = "*com_google_android_material_material*"
-
-    # These are used in WebLayer for HTTP Auth dialog.
-    resource_exclusion_exceptions += [
-      # TextInputLayout
-      "${_material_package}/design_text_*",
-      "${_material_package}/text_*",
-    ]
-
     if (webview_includes_weblayer) {
-      # These are used in WebLayer for the translate infobar
-      resource_exclusion_exceptions +=
-          [ "${_material_package}/design_layout_tab_*" ]
-    }
-
-    # Copied from chrome_public_apk_tmpl.gni.
+      resource_values_filter_rules = weblayer_resource_values_filter_rules
+      resource_exclusion_exceptions += weblayer_resource_exclusion_exceptions
 
-    # Remove unneeded entries from material design values.xml files.
-    resource_values_filter_rules = [
-      "${_material_package}:[Bb]adge",
-      "${_material_package}:[Bb]ottomNavigation",
-      "${_material_package}:[Bb]ottomSheet",
-      "${_material_package}:[Bb]uttonToggleGroup",
-      "${_material_package}:[Cc]alendar",
-      "${_material_package}:[Cc]ardView",
-      "${_material_package}:\b[Cc]hip",
-      "${_material_package}:design_snackbar",
-      "${_material_package}:[Ff]loatingActionButton",
-      "${_material_package}:[Mm]aterialAlertDialog",
-      "${_material_package}:mtrl_alert",
-      "${_material_package}:mtrl_navigation",
-      "${_material_package}:mtrl_slider",
-      "${_material_package}:[Nn]avigationView",
-      "${_material_package}:picker",
-      "${_material_package}:[Ss]nackbar",
-      "${_material_package}:[Ss]lider",
-      "${_material_package}:[Tt]oolbarLayout",
-    ]
-
-    _material_package = "com_google_android_material_material.*"
-
-    # Used only by alert dialog on tiny screens.
-    resource_exclusion_regex += "|${_material_package}values-small"
-
-    # Used only by date picker (which chrome doesn't use).
-    resource_exclusion_regex += "|${_material_package}-(w480dp-port|w360dp-port|h480dp-land|h360dp-land)"
-
-    # Material design layouts that cause views to be kept that we don't use.
-    # Instead of manually filtering, unused resource removal would be better:
-    # https://crbug.com/636448
-    resource_exclusion_regex += "|${_material_package}/layout"
-    resource_exclusion_regex += "|${_material_package}/color.*(choice|chip_|card_|calendar_|bottom_nav_|slider_)"
-    resource_exclusion_regex +=
-        "|${_material_package}/drawable.*design_snackbar"
-    resource_exclusion_regex += "|${_material_package}/xml.*badge_"
+      # Note: WebLayer's resource exclusion regex deliberately does not start
+      # with "|".
+      resource_exclusion_regex += "|" + weblayer_resource_exclusion_regex
+    }
 
     if (!_is_bundle_module) {
       # Used as an additional apk in test scripts.

weblayer/weblayer_resource_exclusions.gni

+# Copyright 2020 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+_material_package = "*com_google_android_material_material*"
+
+weblayer_resource_exclusion_exceptions = [
+  # TextInputLayout (used for HTTP Auth dialog)
+  "${_material_package}/design_text_*",
+  "${_material_package}/text_*",
+
+  # Used for the translate infobar
+  "${_material_package}/design_layout_tab_*",
+]
+
+# Copied from chrome_public_apk_tmpl.gni.
+
+# Remove unneeded entries from material design values.xml files.
+weblayer_resource_values_filter_rules = [
+  "${_material_package}:[Bb]adge",
+  "${_material_package}:[Bb]ottomNavigation",
+  "${_material_package}:[Bb]ottomSheet",
+  "${_material_package}:[Bb]uttonToggleGroup",
+  "${_material_package}:[Cc]alendar",
+  "${_material_package}:[Cc]ardView",
+  "${_material_package}:\b[Cc]hip",
+  "${_material_package}:design_snackbar",
+  "${_material_package}:[Ff]loatingActionButton",
+  "${_material_package}:[Mm]aterialAlertDialog",
+  "${_material_package}:mtrl_alert",
+  "${_material_package}:mtrl_navigation",
+  "${_material_package}:mtrl_slider",
+  "${_material_package}:[Nn]avigationView",
+  "${_material_package}:picker",
+  "${_material_package}:[Ss]nackbar",
+  "${_material_package}:[Ss]lider",
+  "${_material_package}:[Tt]oolbarLayout",
+]
+
+_material_package = "com_google_android_material_material.*"
+
+# Used only by alert dialog on tiny screens.
+weblayer_resource_exclusion_regex = "${_material_package}values-small"
+
+# Used only by date picker (which chrome doesn't use).
+weblayer_resource_exclusion_regex +=
+    "|${_material_package}-(w480dp-port|w360dp-port|h480dp-land|h360dp-land)"
+
+# Material design layouts that cause views to be kept that we don't use.
+# Instead of manually filtering, unused resource removal would be better:
+# https://crbug.com/636448
+weblayer_resource_exclusion_regex += "|${_material_package}/layout"
+weblayer_resource_exclusion_regex += "|${_material_package}/color.*(choice|chip_|card_|calendar_|bottom_nav_|slider_)"
+weblayer_resource_exclusion_regex +=
+    "|${_material_package}/drawable.*design_snackbar"
+weblayer_resource_exclusion_regex += "|${_material_package}/xml.*badge_"