📱 Add enable_chrome_android_internal GN flag

build/config/android/config.gni

Index: build/config/android/config.gni
diff --git a/build/config/android/config.gni b/build/config/android/config.gni
index 2f68c894eb1b36f3f1f0ded5911fbdef497b3e67..a9ff7c46aded784d375a6d6ee7ff74385dd1e571 100644
--- a/build/config/android/config.gni
+++ b/build/config/android/config.gni
@@ -12,7 +12,19 @@ if (is_android) {
                   [ rebase_path("//clank", root_build_dir) ],
                   "string") == "True"
 
-  if (has_chrome_android_internal) {
+  # We are using a separate declare_args block for only this argument so that
+  # we can decide if we have to pull in definitions from the internal config
+  # early.
+  declare_args() {
+    # Enables using the internal Chrome for Android repository. The default
+    # value depends on whether the repository is available, and if it's not but
+    # this argument is manually set to True, the generation will fail.
+    # The main purpose of this argument is to avoid having to maintain 2
+    # repositories to support both public only and internal builds.
+    enable_chrome_android_internal = has_chrome_android_internal
+  }
+
+  if (enable_chrome_android_internal) {
     import("//clank/config.gni")
   }