Fix official build due to 2x.pak reference

chrome/tools/build/win/FILES.cfg

Index: chrome/tools/build/win/FILES.cfg
diff --git a/chrome/tools/build/win/FILES.cfg b/chrome/tools/build/win/FILES.cfg
index 5a9aac63406430bd75aa0c0cdb50c67b4ede5686..c0c7a51a3eac4ffd4e282dbcd3ea609c5bf58e66 100644
--- a/chrome/tools/build/win/FILES.cfg
+++ b/chrome/tools/build/win/FILES.cfg
@@ -352,9 +352,16 @@ FILES = [
     'buildtype': ['dev', 'official'],
   },
   {
+    'filename': 'theme_resources_2x.pak',
+    'arch': ['32bit', '64bit'],
+    'buildtype': ['dev', 'official'],
+    'optional': ['dev', 'official'],
+  },
+  {
     'filename': 'theme_resources_metro_1x.pak',
     'arch': ['32bit', '64bit'],
     'buildtype': ['dev', 'official'],
+    'optional': ['dev', 'official'],
   },
   {
     'filename': 'ui_resources_standard.pak',
@@ -362,6 +369,12 @@ FILES = [
     'buildtype': ['dev', 'official'],
   },
   {
+    'filename': 'ui_resources_2x.pak',
+    'arch': ['32bit', '64bit'],
+    'buildtype': ['dev', 'official'],
+    'optional': ['dev', 'official'],
+  },
+  {
     'filename': 'wow_helper.exe',
     'arch': ['32bit', '64bit'],
     'buildtype': ['dev', 'official'],