Android: Hook up aapt's main dex proguard rules

build/config/android/internal_rules.gni

Index: build/config/android/internal_rules.gni
diff --git a/build/config/android/internal_rules.gni b/build/config/android/internal_rules.gni
index 8002bc085b6c59c3f47efdcef8c26cf34d0c2883..3c0541fb0c0c2ad72ba7120f3202a8a9dd986712 100644
--- a/build/config/android/internal_rules.gni
+++ b/build/config/android/internal_rules.gni
@@ -942,6 +942,14 @@ if (enable_java_templates) {
           rebase_path(main_dex_rules, root_build_dir),
         ]
 
+        if (defined(invoker.extra_main_dex_proguard_config)) {
+          inputs += [ invoker.extra_main_dex_proguard_config ]
+          args += [
+            "--main-dex-rules-path",
+            rebase_path(invoker.extra_main_dex_proguard_config, root_build_dir),
+          ]
+        }
+
         if (defined(invoker.args)) {
           args += invoker.args
         }
@@ -2702,6 +2710,14 @@ if (enable_java_templates) {
         ]
       }
 
+      if (defined(invoker.proguard_file_main_dex)) {
+        outputs += [ invoker.proguard_file_main_dex ]
+        args += [
+          "--proguard-file-main-dex",
+          rebase_path(invoker.proguard_file_main_dex, root_build_dir),
+        ]
+      }
+
       if (defined(invoker.args)) {
         args += invoker.args
       }