CrOS: Add DeviceEventLogErrorBrowserTest

This test is intended to ensure that no errors are logged to
DeviceEventLog under normal conditions. Currently this will only run
on linux-chromeos. A similar Tast test will also be added to cover
running on a device.

Bug: 550539
Change-Id: I2f100cefb396d074c448c862d3a8908e11b07243
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2284072
Commit-Queue: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#785934}

chrome/browser/chromeos/net/device_event_log_error_browsertest.cc

+// Copyright 2020 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 <memory>
+
+#include "chrome/browser/chromeos/login/login_manager_test.h"
+#include "chrome/browser/chromeos/login/test/login_manager_mixin.h"
+#include "components/account_id/account_id.h"
+#include "components/device_event_log/device_event_log.h"
+#include "content/public/test/browser_test.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+// Browser test using device_event_log to ensure that no device related error
+// events are generated during startup and after login.
+
+namespace chromeos {
+
+class DeviceEventLogErrorBrowserTest : public LoginManagerTest {
+ public:
+  DeviceEventLogErrorBrowserTest() {
+    set_should_launch_browser(true);
+    login_mixin_.AppendRegularUsers(1);
+  }
+  DeviceEventLogErrorBrowserTest(const DeviceEventLogErrorBrowserTest&) =
+      delete;
+  DeviceEventLogErrorBrowserTest& operator=(
+      const DeviceEventLogErrorBrowserTest&) = delete;
+  ~DeviceEventLogErrorBrowserTest() override = default;
+
+  int GetErrors() {
+    return device_event_log::GetCountByLevelForTesting(
+        device_event_log::LogLevel::LOG_LEVEL_ERROR);
+  }
+
+ protected:
+  LoginManagerMixin login_mixin_{&mixin_host_};
+};
+
+IN_PROC_BROWSER_TEST_F(DeviceEventLogErrorBrowserTest, Startup) {
+  EXPECT_EQ(GetErrors(), 0);
+}
+
+IN_PROC_BROWSER_TEST_F(DeviceEventLogErrorBrowserTest, LoginUser) {
+  LoginUser(login_mixin_.users()[0].account_id);
+  EXPECT_EQ(GetErrors(), 0);
+}
+
+}  // namespace chromeos

chrome/test/BUILD.gn

@@ -2349,6 +2349,7 @@ if (!is_android) {
         "../browser/chromeos/login/web_kiosk_controller_browsertest.cc",
         "../browser/chromeos/login/webview_login_browsertest.cc",
         "../browser/chromeos/login/wizard_controller_browsertest.cc",
+        "../browser/chromeos/net/device_event_log_error_browsertest.cc",
         "../browser/chromeos/net/network_portal_detector_impl_browsertest.cc",
         "../browser/chromeos/network_change_manager_client_browsertest.cc",
         "../browser/chromeos/platform_keys/platform_keys_service_browsertest.cc",

components/device_event_log/device_event_log.cc

@@ -87,6 +87,10 @@ void Clear(const base::Time& begin, const base::Time& end) {
     g_device_event_log->Clear(begin, end);
 }
 
+int GetCountByLevelForTesting(LogLevel level) {
+  return g_device_event_log->GetCountByLevelForTesting(level);
+}
+
 namespace internal {
 
 DeviceEventLogInstance::DeviceEventLogInstance(const char* file,

components/device_event_log/device_event_log.h

@@ -80,7 +80,8 @@
 
 #define DEVICE_LOG(type, level)                                            \
   ::device_event_log::internal::DeviceEventLogInstance(__FILE__, __LINE__, \
-                                                       type, level).stream()
+                                                       type, level)        \
+      .stream()
 #define DEVICE_PLOG(type, level)                                            \
   ::device_event_log::internal::DeviceEventSystemErrorLogInstance(          \
       __FILE__, __LINE__, type, level, ::logging::GetLastSystemErrorCode()) \
@@ -192,6 +193,8 @@ void DEVICE_EVENT_LOG_EXPORT Clear(const base::Time& begin,
 
 DEVICE_EVENT_LOG_EXPORT extern const LogLevel kDefaultLogLevel;
 
+int DEVICE_EVENT_LOG_EXPORT GetCountByLevelForTesting(LogLevel level);
+
 namespace internal {
 
 // Implementation class for DEVICE_LOG macros. Provides a stream for creating

components/device_event_log/device_event_log_impl.cc

@@ -471,6 +471,15 @@ void DeviceEventLogImpl::Clear(const base::Time& begin, const base::Time& end) {
   entries_.erase(begin_it, end_rev_it.base());
 }
 
+int DeviceEventLogImpl::GetCountByLevelForTesting(LogLevel level) {
+  int count = 0;
+  for (const auto& entry : entries_) {
+    if (entry.log_level == level)
+      ++count;
+  }
+  return count;
+}
+
 DeviceEventLogImpl::LogEntry::LogEntry(const char* filedesc,
                                        int file_line,
                                        LogType log_type,

components/device_event_log/device_event_log_impl.h

@@ -75,6 +75,8 @@ class DEVICE_EVENT_LOG_EXPORT DeviceEventLogImpl {
   void ClearAll();
   void Clear(const base::Time& begin, const base::Time& end);
 
+  int GetCountByLevelForTesting(LogLevel level);
+
   // Called from device_event_log::AddEntry if the global instance has not been
   // created (or has already been destroyed). Logs to LOG(ERROR) or VLOG(1).
   static void SendToVLogOrErrorLog(const char* file,