Always persist histograms from setup.exe.

chrome/installer/setup/persistent_histogram_storage.h

 // Copyright 2016 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.
 
-#ifndef CHROME_TEST_BASE_MOJO_TEST_CONNECTOR_H_
-#define CHROME_TEST_BASE_MOJO_TEST_CONNECTOR_H_
+#ifndef CHROME_INSTALLER_SETUP_PERSISTENT_HISTOGRAM_STORAGE_H_
+#define CHROME_INSTALLER_SETUP_PERSISTENT_HISTOGRAM_STORAGE_H_
 
-#include <memory>
+#include "base/files/file_path.h"
+#include "base/macros.h"
 
-#include "base/macros.h"
-#include "base/process/process_handle.h"
-#include "base/test/launcher/test_launcher.h"
-#include "services/shell/background/background_shell.h"
-#include "services/shell/public/interfaces/service.mojom.h"
+namespace installer {
 
-namespace base {
-class CommandLine;
-}
+// When a PersistentHistogramStorage is destructed, histograms recorded during
+// its lifetime are persisted in the directory set by set_storage_dir().
+// Histograms are not persisted if set_storage_dir() has not been called or if
+// the storage directory does not exist on destruction.
+// PersistentHistogramStorage should be instantiated as early as possible in the
+// process lifetime and should never be instantiated again. Persisted histograms
+// will eventually be reported by the browser process.
+class PersistentHistogramStorage {
+ public:
+  PersistentHistogramStorage();
+  ~PersistentHistogramStorage();
 
-namespace content {
-class TestState;
-}
+  // Sets |storage_dir| as the directory in which histograms will be persisted
+  // when this PersistentHistogramStorage is destructed.
+  void set_storage_dir(const base::FilePath& storage_dir) {
+    storage_dir_ = storage_dir;
+  }
 
-// MojoTestConnector in responsible for providing the necessary wiring for
-// test processes to get a mojo channel passed to them.  To use this class
-// call PrepareForTest() prior to launching each test. It is expected
-// PrepareForTest() is called from content::TestLauncherDelegate::PreRunTest().
-class MojoTestConnector {
- public:
-  // Switch added to command line of each test.
-  static const char kTestSwitch[];
-
-  // Command line switch added to all apps that are expected to be provided by
-  // browser_tests.
-  static const char kMashApp[];
-
-  MojoTestConnector();
-  ~MojoTestConnector();
-
-  // Initializes the background thread the Shell runs on.
-  shell::mojom::ServiceRequest Init();
-
-  std::unique_ptr<content::TestState> PrepareForTest(
-      base::CommandLine* command_line,
-      base::TestLauncher::LaunchOptions* test_launch_options);
+  // Returns a directory in which setup histograms must be persisted to be
+  // reported by a product installed in |target_path|. Should be used as
+  // argument to set_storage_dir().
+  static base::FilePath GetReportedStorageDir(
+      const base::FilePath& target_path);
 
  private:
-  class NativeRunnerDelegateImpl;
+  base::FilePath storage_dir_;
 
-  std::unique_ptr<NativeRunnerDelegateImpl> native_runner_delegate_;
-
-  shell::BackgroundShell background_shell_;
-
-  DISALLOW_COPY_AND_ASSIGN(MojoTestConnector);
+  DISALLOW_COPY_AND_ASSIGN(PersistentHistogramStorage);
 };
 
-#endif  // CHROME_TEST_BASE_MOJO_TEST_CONNECTOR_H_
+}  // namespace installer
+
+#endif  // CHROME_INSTALLER_SETUP_PERSISTENT_HISTOGRAM_STORAGE_H_