Allow browser tests to run with dynamic CLD data.

chrome/browser/translate/translate_browser_test_utils.h

+// Copyright 2014 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_BROWSER_TRANSLATE_TRANSLATE_BROWSER_TEST_UTILS_H_
+#define CHROME_BROWSER_TRANSLATE_TRANSLATE_BROWSER_TEST_UTILS_H_
+
+#include "base/macros.h"
+
+namespace test {
+
+// A utility class that sets up CLD dynamic data when constructed, and cleans
+// it up when destroyed.
+class ScopedCLDDynamicDataHarness {
+ public:
+  // Invokes whatever dark magic is required in order to make the CLD data
+  // available immediately to testing code. The implementation may vary
+  // depending on the following defines, bypassing any external data access
+  // requirements. In pseudocode, this looks like the following:
+  //
+  // CLD_VERSION=2 && defined(CLD2_DYNAMIC_MODE) && !defined(CLD2_IS_COMPONENT):

[Takashi Toyoshima, 2014/05/19 14:32:24]

I feel these comments are not useful for developers who use this harness, but
needed for developers who modify implementations. So, moving these details aside
implementation side in .cc will be useful.

WDYT? This is just my preference, so it is up to you.

[Andrew Hayden (chromium.org), 2014/05/19 15:14:21]

Done.

+  //   Copy the CLD data file from test data into it's default location:
+  //     ${chrome::DIR_USER_DATA}/${chrome::kCLDDataFilename}
+  //
+  // CLD_VERSION=2 && defined(CLD2_DYNAMIC_MODE) && defined(CLD2_IS_COMPONENT):
+  //   Copy the CLD CRX contents from test data into a realistic location:
+  //     ${chrome::DIR_USER_DATA}/${chrome::DIR_COMPONENT_CLD2}/${VERSION}
+  //   Call CldComponentInstallerTraits::SetLatestCldDataFile(...)
+  //
+  // In all other cases, the code does nothing because the CLD data is already
+  // statically linked into the executable.
+  //
+  // The data for this class lives under:
+  //   src/chrome/test/data/cld2_component
+  ScopedCLDDynamicDataHarness();
+
+  // Reverses the work done by the constructor: any files and/or directories
+  // that would be created by the constructor are immediately and irrevocably
+  // deleted.
+  //
+  // If dynamic data is not currently available for any reason, this method has
+  // no net effect on the runtime.
+  ~ScopedCLDDynamicDataHarness();
+
+ private:

[Takashi Toyoshima, 2014/05/19 14:32:24]

These three methods can be static, or functions inside anonymous namespace in
the implementation file.

[Andrew Hayden (chromium.org), 2014/05/19 15:14:21]

Done.

+  void MakeDynamicCLDDataAvailableForTest();
+  void MakeDynamicCLDDataUnavailableForTest();
+  void ClearStandaloneFileState();
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedCLDDynamicDataHarness);
+};
+
+}  // namespace test
+
+#endif  // CHROME_BROWSER_TRANSLATE_TRANSLATE_BROWSER_TEST_UTILS_H_