android: Check that we do not include the same resource in multiple pak files.

chrome/chrome_android_paks.gypi

Index: chrome/chrome_android_paks.gypi
diff --git a/chrome/chrome_android_paks.gypi b/chrome/chrome_android_paks.gypi
index 13f5845ac2079234659c8e2633eff5b929f9d3f1..55feb0fe7fbaf644862fbb69d7026f047c68ae7a 100644
--- a/chrome/chrome_android_paks.gypi
+++ b/chrome/chrome_android_paks.gypi
@@ -4,9 +4,11 @@
 {
   'variables': {
     'chrome_android_pak_output_folder': '<@(PRODUCT_DIR)/../assets/<(package_name)',
-    'chrome_android_pak_input_resources': [
+    'chrome_android_pak_unique_resources': [
       '<(PRODUCT_DIR)/resources.pak',
       '<(PRODUCT_DIR)/chrome_100_percent.pak',
+    ],
+    'chrome_android_pak_language_resources': [
       '<(PRODUCT_DIR)/locales/am.pak',
       '<(PRODUCT_DIR)/locales/ar.pak',
       '<(PRODUCT_DIR)/locales/bg.pak',
@@ -52,6 +54,10 @@
       '<(PRODUCT_DIR)/locales/zh-CN.pak',
       '<(PRODUCT_DIR)/locales/zh-TW.pak',
     ],
+    'chrome_android_pak_input_resources': [
+      '<@(chrome_android_pak_language_resources)',
+      '<@(chrome_android_pak_unique_resources)',
+    ],
     'chrome_android_pak_output_resources': [
       '<(chrome_android_pak_output_folder)/resources.pak',
       '<(chrome_android_pak_output_folder)/chrome_100_percent.pak',
@@ -129,6 +135,16 @@
         '<(DEPTH)/chrome/chrome_resources.gyp:packed_resources',
         '<(DEPTH)/chrome/chrome_resources.gyp:packed_extra_resources',
       ],
+      'actions': [{
+        'action_name': 'check for duplicate resources',
+        'inputs': [ '<@(chrome_android_pak_unique_resources)', ],
+        'outputs': [ '<(PRODUCT_DIR)/check_dups_<(package_name).stamp' ],
+        'action': [
+            'python',
+            '<(DEPTH)/tools/grit/grit/format/check_dups.py',
+            '<@(chrome_android_pak_unique_resources)',
+        ],
+      }],
       'copies': [
         {
           'destination': '<(chrome_android_pak_output_folder)',