resources: Prevent including the same resource in multiple pack files.

components/test/run_all_unittests.cc

Index: components/test/run_all_unittests.cc
diff --git a/components/test/run_all_unittests.cc b/components/test/run_all_unittests.cc
index 5cd4102f9f55014ecf5422a1ef4e9e39de409cb2..ae770949ab92362e4251c1aa78acc8dff937527e 100644
--- a/components/test/run_all_unittests.cc
+++ b/components/test/run_all_unittests.cc
@@ -61,8 +61,19 @@ class ComponentsTestSuite : public base::TestSuite {
 #else
     PathService::Get(base::DIR_MODULE, &pak_path);
 #endif
+
+#if defined(OS_IOS) || defined(OS_ANDROID)
     ui::ResourceBundle::InitSharedInstanceWithPakPath(
         pak_path.AppendASCII("components_tests_resources.pak"));
+#else
+    base::FilePath ui_test_pak_path;
+    ASSERT_TRUE(PathService::Get(ui::UI_TEST_PAK, &ui_test_pak_path));
+    ui::ResourceBundle::InitSharedInstanceWithPakPath(ui_test_pak_path);
+
+    ui::ResourceBundle::GetSharedInstance().AddDataPackFromPath(
+        pak_path.AppendASCII("components_tests_resources.pak"),
+        ui::SCALE_FACTOR_NONE);
+#endif
 
     // These schemes need to be added globally to pass tests of
     // autocomplete_input_unittest.cc and content_settings_pattern*