[DevUI DFM] Implement hierarchical PAK scheme via dev_ui_page_resources.pak.

This CL restructures PAK inclusion for DevUI pages to be hierarchical:
* Each DevUI page has its own "atomic" PAK files (currently only done
  for chrome://bluetooth-internals).
* On *all* architectures, pages intended for the DevUI DFM are repacked
  into dev_ui_page_resources.pak.
* For non-Android, or if DevUI DFM is off, dev_ui_page_resources.pak is
  simply repacked with other resources to form resources.pak. This
  produces the same result as before.
* For Android with DevUI DFM on (APK and bundles):
  * dev_ui_page_resources.pak and DevUI support resources are repacked
    into dev_ui_resources.pak.
  * Remaining resources go into resources.pak.

This CL also centralizes atomic PAK files targets and deps into a single
target (dev_ui_paks) in chrome/browser/resources/BUILD.gn, making it
easier to edit dev_ui_page_resources.pak contents.

Change-Id: Ieeaa18a322b46ed5102b2cbec20fab44a2b4ab82
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1785007Reviewed-by: Tibor Goldschwendt <tiborg@chromium.org>
Reviewed-by: Dan Beam <dbeam@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Commit-Queue: Samuel Huang <huangs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#699997}

chrome/BUILD.gn

@@ -1524,10 +1524,10 @@ group("extra_resources") {
   if (!is_android) {
     public_deps += [
       "//chrome/browser/resources:component_extension_resources",
+      "//chrome/browser/resources:dev_ui_paks",
       "//chrome/browser/resources:downloads_resources",
       "//chrome/browser/resources:local_ntp_resources",
       "//chrome/browser/resources:settings_resources",
-      "//chrome/browser/resources/bluetooth_internals:resources",
     ]
   }
 

chrome/android/BUILD.gn

@@ -1381,8 +1381,8 @@ if (current_toolchain == default_toolchain) {
       }
       if (!dfmify_dev_ui) {
         additional_extra_paks +=
-            [ "$root_gen_dir/chrome/bluetooth_internals_resources.pak" ]
-        deps += [ "//chrome/browser/resources/bluetooth_internals:resources" ]
+            [ "$root_gen_dir/chrome/dev_ui_page_resources.pak" ]
+        deps += [ "//chrome/browser/resources:dev_ui_paks" ]
       }
 
       if (enable_resource_whitelist_generation) {

chrome/android/features/dev_ui/BUILD.gn

@@ -22,11 +22,10 @@ android_library("java") {
 }
 
 android_assets("pak_assets") {
-  renaming_sources =
-      [ "$root_gen_dir/chrome/bluetooth_internals_resources.pak" ]
+  renaming_sources = [ "$root_gen_dir/chrome/dev_ui_page_resources.pak" ]
   renaming_destinations = [ "dev_ui_resources.pak" ]
   deps = [
-    "//chrome/browser/resources/bluetooth_internals:resources",
+    "//chrome/browser/resources:dev_ui_paks",
   ]
   disable_compression = true
 }

chrome/browser/resources/BUILD.gn

@@ -4,6 +4,7 @@
 
 import("//chrome/common/features.gni")
 import("//tools/grit/grit_rule.gni")
+import("//tools/grit/repack.gni")
 
 assert(!is_ios, "Chromium/iOS shouldn't use anything in //chrome")
 
@@ -340,3 +341,14 @@ if (enable_webui_tab_strip) {
     ]
   }
 }
+
+repack("dev_ui_paks") {
+  output = "$root_gen_dir/chrome/dev_ui_page_resources.pak"
+
+  sources = [
+    "$root_gen_dir/chrome/bluetooth_internals_resources.pak",
+  ]
+  deps = [
+    "//chrome/browser/resources/bluetooth_internals:resources",
+  ]
+}

chrome/chrome_paks.gni

@@ -135,8 +135,8 @@ template("chrome_extra_paks") {
     } else {
       # New paks should be added here by default.
       sources += [
-        "$root_gen_dir/chrome/bluetooth_internals_resources.pak",
         "$root_gen_dir/chrome/component_extension_resources.pak",
+        "$root_gen_dir/chrome/dev_ui_page_resources.pak",
         "$root_gen_dir/chrome/downloads_resources.pak",
         "$root_gen_dir/chrome/local_ntp_resources.pak",
         "$root_gen_dir/chrome/settings_resources.pak",
@@ -145,10 +145,10 @@ template("chrome_extra_paks") {
       ]
       deps += [
         "//chrome/browser/resources:component_extension_resources",
+        "//chrome/browser/resources:dev_ui_paks",
         "//chrome/browser/resources:downloads_resources",
         "//chrome/browser/resources:local_ntp_resources",
         "//chrome/browser/resources:settings_resources",
-        "//chrome/browser/resources/bluetooth_internals:resources",
         "//content/browser/devtools:devtools_resources",
         "//headless:resources",
       ]