Enable proguard for apks

build/config/android/rules.gni

 # Copyright 2014 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.
 
 import("//base/android/linker/config.gni")
 import("//build/config/android/config.gni")
 import("//build/config/android/internal_rules.gni")
 import("//tools/grit/grit_rule.gni")
 import("//tools/relocation_packer/config.gni")
 
@@ skipping 1285 matching lines @@
   _android_manifest = invoker.android_manifest
   _rebased_build_config = rebase_path(_build_config, root_build_dir)
   _create_abi_split =
       defined(invoker.create_abi_split) && invoker.create_abi_split
   _create_density_splits =
       defined(invoker.create_density_splits) && invoker.create_density_splits
 
   # Help GN understand that _create_abi_split is not unused (bug in GN).
   assert(_create_abi_split || true)
 
+  _proguard_enabled = false
+  if (defined(invoker.proguard_enabled) && invoker.proguard_enabled) {
+    _proguard_enabled = true
+    _proguard_jar_path = "$base_path.proguard.jar"
+  }
+
   write_build_config("${_template_name}__build_config") {
     type = "android_apk"
     dex_path = final_dex_path
     resources_zip = resources_zip_path
     build_config = _build_config
     android_manifest = _android_manifest
 
     if (defined(invoker.deps)) {
       deps = invoker.deps
     }
 
     if (defined(invoker.apk_under_test)) {
       apk_under_test = invoker.apk_under_test
     }
 
+    if (_proguard_enabled) {
+      proguard_enabled = true
+      proguard_info = "$_proguard_jar_path.info"
+    }
+
     native_libs = _native_libs
   }
 
   final_deps = []
 
   final_deps += [ ":${_template_name}__process_resources" ]
+  _generated_proguard_config = "$base_path.resources.proguard.txt"
   process_resources("${_template_name}__process_resources") {
     srcjar_path = "${target_gen_dir}/${target_name}.srcjar"
     r_text_path = "${target_gen_dir}/${target_name}_R.txt"
     android_manifest = _android_manifest
     resource_dirs = [ "//build/android/ant/empty/res" ]
     zip_path = resources_zip_path
     all_resources_zip_path = _all_resources_zip_path
     generate_constant_ids = true
+    proguard_file = _generated_proguard_config
     build_config = _build_config
 
     if (defined(invoker.include_all_resources)) {
       include_all_resources = invoker.include_all_resources
     }
   }
   _srcjar_deps += [ ":${_template_name}__process_resources" ]
 
   if (_native_libs != []) {
     _enable_chromium_linker_tests = false
@@ skipping 69 matching lines @@
         rebase_path(_dist_jar_path, root_build_dir),
         "--inputs=@FileArg($_rebased_build_config:dist_jar:dependency_jars)",
       ]
       inputs += [ jar_path ]
       _rebased_jar_path = rebase_path([ jar_path ], root_build_dir)
       args += [ "--inputs=$_rebased_jar_path" ]
     }
   }
 
   final_deps += [ ":${_template_name}__final_dex" ]
+
+  dex_jar_path = jar_path
+  if (defined(invoker.proguard_enabled) && invoker.proguard_enabled) {
+    _proguard_configs = [ _generated_proguard_config ]
+    if (defined(invoker.proguard_configs)) {
+      _proguard_configs += invoker.proguard_configs
+    }
+    proguard("${_template_name}__proguard") {
+      inputs = [

[newt (away), 2015/05/29 01:43:04]

funky indentation. this would be more normal:

    inputs = [
      _build_config,
      jar_path,
    ] + _proguard_configs

+                 _build_config,
+                 jar_path,
+               ] + _proguard_configs
+
+      output_jar_path = _proguard_jar_path
+      rebased_proguard_configs = rebase_path(_proguard_configs, root_build_dir)
+      args = [
+        "--proguard-configs=$rebased_proguard_configs",
+        "--tested-apk-info=@FileArg($_rebased_build_config:proguard:tested_apk_info)",
+        "--input-paths=@FileArg($_rebased_build_config:proguard:input_paths)",
+      ]
+    }
+    dex_jar_path = _proguard_jar_path
+  }
+
   dex("${_template_name}__final_dex") {
     deps = [
       ":${_template_name}__java",
     ]
     sources = [
-      jar_path,
+      dex_jar_path,
     ]
     inputs = [
       _build_config,
     ]
     output = final_dex_path
     dex_arg_key = "${_rebased_build_config}:final_dex:dependency_dex_files"
     args = [ "--inputs=@FileArg($dex_arg_key)" ]
   }
 
   if (_native_libs != []) {
@@ skipping 423 matching lines @@
 template("uiautomator_test") {
   set_sources_assignment_filter([])
   if (defined(invoker.testonly)) {
     testonly = invoker.testonly
   }
   assert(target_name != "")
   assert(invoker.deps != [] || true)
   group(target_name) {
   }
 }