Add a browser test to verify the policy value in prefs.

This test verifies the policy value is read and copied to local_state properly in the early
stage of browser launch on Windows.

It's a test for the patch: crrev.com/615e458c.

Bug: 806538
Change-Id: I5b150f7429f968312692123d5d40525c3ddbd9c6
Reviewed-on: https://chromium-review.googlesource.com/892043
Commit-Queue: Owen Min <zmin@chromium.org>
Reviewed-by: Maksim Ivanov <emaxx@chromium.org>
Cr-Commit-Position: refs/heads/master@{#533083}

chrome/browser/policy/policy_initialization_browsertest.cc

+// Copyright 2018 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.
+
+#include <string>
+
+#include "base/macros.h"
+#include "base/strings/string16.h"
+#include "base/strings/utf_string_conversions.h"
+#include "build/build_config.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/chrome_browser_main.h"
+#include "chrome/browser/chrome_browser_main_extra_parts.h"
+#include "chrome/common/pref_names.h"
+#include "chrome/test/base/in_process_browser_test.h"
+#include "components/policy/policy_constants.h"
+#include "components/prefs/pref_service.h"
+
+#if defined(OS_WIN)
+#include <windows.h>
+#include "base/test/test_reg_util_win.h"
+#include "base/win/registry.h"
+#endif
+
+namespace {
+
+#if defined(OS_WIN)
+const char kMockPolicyName[] = "AllowFileSelectionDialogs";
+#endif
+
+void VerifyLocalState() {
+  const PrefService* prefs = g_browser_process->local_state();
+  ASSERT_NE(nullptr, prefs);
+  const PrefService::Preference* pref =
+      prefs->FindPreference(prefs::kAllowFileSelectionDialogs);
+  ASSERT_NE(nullptr, pref);
+  EXPECT_FALSE(pref->IsDefaultValue());
+}
+
+class ChromeBrowserMainExtraPartsPolicyValueChecker
+    : public ChromeBrowserMainExtraParts {
+ public:
+  ChromeBrowserMainExtraPartsPolicyValueChecker() {}
+
+  // ChromeBrowserMainExtraParts
+  void PreCreateThreads() override { VerifyLocalState(); }
+  void PreBrowserStart() override { VerifyLocalState(); }
+  void PreMainMessageLoopRun() override { VerifyLocalState(); }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ChromeBrowserMainExtraPartsPolicyValueChecker);
+};
+
+}  // namespace
+
+// Test if the policy value can be read from the pref properly on Windows.
+class PolicyInitializationBrowserTest : public InProcessBrowserTest {
+ protected:
+  PolicyInitializationBrowserTest() {}
+
+  // content::BrowserTestBase:
+  void SetUpInProcessBrowserTestFixture() override {
+    SetUpPlatformPolicyValue();
+  }
+  void CreatedBrowserMainParts(content::BrowserMainParts* parts) override {
+    static_cast<ChromeBrowserMainParts*>(parts)->AddParts(
+        new ChromeBrowserMainExtraPartsPolicyValueChecker());
+  }
+
+ private:
+#if defined(OS_WIN)
+  // Set up policy value for windows platform
+  void SetUpPlatformPolicyValue() {
+    HKEY root = HKEY_CURRENT_USER;
+    ASSERT_NO_FATAL_FAILURE(registry_override_manager_.OverrideRegistry(root));
+
+    base::win::RegKey key;
+
+    ASSERT_EQ(ERROR_SUCCESS, key.Create(root, policy::kRegistryChromePolicyKey,
+                                        KEY_SET_VALUE | KEY_WOW64_32KEY));
+    ASSERT_EQ(ERROR_SUCCESS,
+              key.WriteValue(base::ASCIIToUTF16(kMockPolicyName).c_str(), 1));
+  }
+
+  registry_util::RegistryOverrideManager registry_override_manager_;
+#else
+  // This test hasn't supported other platform yet.
+  void SetUpPlatformPolicyValue() {}
+#endif
+
+  DISALLOW_COPY_AND_ASSIGN(PolicyInitializationBrowserTest);
+};
+
+#if defined(OS_WIN)
+IN_PROC_BROWSER_TEST_F(PolicyInitializationBrowserTest, VerifyLocalState) {
+  VerifyLocalState();
+}
+#endif

chrome/test/BUILD.gn

@@ -627,6 +627,7 @@ test("browser_tests") {
       "../browser/policy/cloud/test_request_interceptor.cc",
       "../browser/policy/cloud/test_request_interceptor.h",
       "../browser/policy/policy_browsertest.cc",
+      "../browser/policy/policy_initialization_browsertest.cc",
       "../browser/policy/policy_network_browsertest.cc",
       "../browser/policy/policy_prefs_browsertest.cc",
       "../browser/policy/policy_startup_browsertest.cc",