Do not disable guest mode when BrowserSignin override ForceBrowesrSignin without a forced value

Bug: 894212
Change-Id: Icd4c7d9f8a79a9b57900366d4677b0e7023b8ca3
Reviewed-on: https://chromium-review.googlesource.com/c/1274196
Commit-Queue: Owen Min <zmin@chromium.org>
Reviewed-by: Mihai Sardarescu <msarda@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599247}

chrome/browser/profiles/guest_mode_policy_handler.cc

@@ -32,8 +32,10 @@ void GuestModePolicyHandler::ApplyPolicySettings(const PolicyMap& policies,
   const base::Value* browser_signin_value =
       policies.GetValue(key::kBrowserSignin);
   int int_browser_signin_value;
-  if (browser_signin_value &&
-      browser_signin_value->GetAsInteger(&int_browser_signin_value) &&
+  bool is_browser_signin_policy_set =
+      (browser_signin_value &&
+       browser_signin_value->GetAsInteger(&int_browser_signin_value));
+  if (is_browser_signin_policy_set &&
       static_cast<BrowserSigninMode>(int_browser_signin_value) ==
           BrowserSigninMode::kForced) {
     prefs->SetBoolean(prefs::kBrowserGuestModeEnabled, false);
@@ -43,7 +45,7 @@ void GuestModePolicyHandler::ApplyPolicySettings(const PolicyMap& policies,
   const base::Value* force_signin_value =
       policies.GetValue(key::kForceBrowserSignin);
   bool is_force_signin_enabled;
-  if (force_signin_value &&
+  if (!is_browser_signin_policy_set && force_signin_value &&
       force_signin_value->GetAsBoolean(&is_force_signin_enabled) &&
       is_force_signin_enabled) {
     prefs->SetBoolean(prefs::kBrowserGuestModeEnabled, false);

chrome/browser/profiles/guest_mode_policy_handler_unittest.cc

@@ -5,6 +5,7 @@
 #include "chrome/browser/profiles/guest_mode_policy_handler.h"
 
 #include "base/values.h"
+#include "chrome/browser/policy/browser_signin_policy_handler.h"
 #include "chrome/common/pref_names.h"
 #include "components/policy/core/common/policy_map.h"
 #include "components/policy/policy_constants.h"
@@ -85,4 +86,39 @@ TEST_F(GuestModePolicyHandlerTest, GuestModeSet) {
   EXPECT_FALSE(value);
 }
 
+TEST_F(GuestModePolicyHandlerTest, GuestModeDisabledWhenBrowserSigninIsForced) {
+  SetUpPolicy(key::kBrowserSignin,
+              static_cast<int>(BrowserSigninMode::kForced));
+  handler_.ApplyPolicySettings(policies_, &prefs_);
+  bool value = true;
+  EXPECT_TRUE(prefs_.GetBoolean(prefs::kBrowserGuestModeEnabled, &value));
+  EXPECT_FALSE(value);
+}
+
+TEST_F(GuestModePolicyHandlerTest,
+       GuestModeIsNotSetWhenBrowserSigninIsNotForced) {
+  bool value = false;
+  SetUpPolicy(key::kBrowserSignin,
+              static_cast<int>(BrowserSigninMode::kEnabled));
+  handler_.ApplyPolicySettings(policies_, &prefs_);
+  EXPECT_FALSE(prefs_.GetBoolean(prefs::kBrowserGuestModeEnabled, &value));
+
+  SetUpPolicy(key::kBrowserSignin,
+              static_cast<int>(BrowserSigninMode::kDisabled));
+  handler_.ApplyPolicySettings(policies_, &prefs_);
+  EXPECT_FALSE(prefs_.GetBoolean(prefs::kBrowserGuestModeEnabled, &value));
+
+  // Invalid format
+  SetUpPolicy(key::kBrowserSignin, false);
+  handler_.ApplyPolicySettings(policies_, &prefs_);
+  EXPECT_FALSE(prefs_.GetBoolean(prefs::kBrowserGuestModeEnabled, &value));
+
+  // Even with forceBrowserSignin enable.
+  SetUpPolicy(key::kBrowserSignin,
+              static_cast<int>(BrowserSigninMode::kEnabled));
+  SetUpPolicy(key::kForceBrowserSignin, true);
+  handler_.ApplyPolicySettings(policies_, &prefs_);
+  EXPECT_FALSE(prefs_.GetBoolean(prefs::kBrowserGuestModeEnabled, &value));
+}
+
 }  // namespace policy