Integrate fallback crash handling in chrome

components/crash/content/app/fallback_crash_handling_win_unittest.cc

+// Copyright 2017 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 "components/crash/content/app/fallback_crash_handling_win.h"
+
+#include "base/base_switches.h"
+#include "base/command_line.h"
+#include "base/files/file_path.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/logging.h"
+#include "base/test/multiprocess_test.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/multiprocess_func_list.h"
+#include "third_party/crashpad/crashpad/client/crash_report_database.h"
+
+namespace crash_reporter {
+
+namespace {
+
+const DWORD kExceptionCode = 0xCAFEBABE;
+
+// This main function runs in two modes, first as a faux-crashpad handler,
+// and then with --type=fallback-handler to handle the crash in the first
+// instance.
+MULTIPROCESS_TEST_MAIN(FallbackCrashHandlingWinRunHandler) {
+  base::CommandLine* cmd_line = base::CommandLine::ForCurrentProcess();
+  if (cmd_line->GetSwitchValueASCII("type") ==
+      switches::kFallbackCrashHandler) {
+    return RunAsFallbackCrashHandler(*cmd_line,
+                                     "FallbackCrashHandlingWinRunHandler",
+                                     "1.2.3.4", "FakeChannel");
+  }
+
+  CHECK(SetupFallbackCrashHandling(*cmd_line));
+
+  // Provoke a crash with a well-defined exception code.
+  // The process shouldn't terminate with this exception code.
+  RaiseException(kExceptionCode, 0, 0, nullptr);
+
+  // This process should never return from the exception.
+  CHECK(false) << "Unexpected return from RaiseException";
+
+  // Should never get here.
+  return 0;
+}
+
+class FallbackCrashHandlingTest : public base::MultiProcessTest {
+ public:
+  void SetUp() override { ASSERT_TRUE(database_dir_.CreateUniqueTempDir()); }
+
+ protected:
+  base::ScopedTempDir database_dir_;
+};
+
+}  // namespace
+
+TEST_F(FallbackCrashHandlingTest, SetupAndRunAsFallbackCrashHandler) {
+  // Launch a subprocess to

[scottmg, 2017/01/16 18:40:29]

Finish this comment.

[Sigurður Ásgeirsson, 2017/01/16 18:52:44]

Done.

+  base::CommandLine cmd_line = base::GetMultiProcessTestChildBaseCommandLine();
+  cmd_line.AppendSwitchPath("database", database_dir_.GetPath());
+
+  base::LaunchOptions options;
+  options.start_hidden = true;
+  base::Process test_child = base::SpawnMultiProcessTestChild(
+      "FallbackCrashHandlingWinRunHandler", cmd_line, options);
+
+  ASSERT_TRUE(test_child.IsValid());
+  int exit_code = -1;
+  ASSERT_TRUE(test_child.WaitForExit(&exit_code));
+  ASSERT_EQ(kFallbackCrashTerminationCode, exit_code);
+
+  // Validate that the database contains one valid crash dump.
+  std::unique_ptr<crashpad::CrashReportDatabase> database =
+      crashpad::CrashReportDatabase::InitializeWithoutCreating(
+          database_dir_.GetPath());
+
+  std::vector<crashpad::CrashReportDatabase::Report> reports;
+  ASSERT_EQ(crashpad::CrashReportDatabase::kNoError,
+            database->GetPendingReports(&reports));
+
+  EXPECT_EQ(1U, reports.size());
+}
+
+}  // namespace crash_reporter