Add translate client mock.

components/translate/core/browser/mock_translate_client.h

Index: components/translate/core/browser/mock_translate_client.h
diff --git a/components/translate/core/browser/mock_translate_client.h b/components/translate/core/browser/mock_translate_client.h
new file mode 100644
index 0000000000000000000000000000000000000000..6e6fac1829f2a1e38d45a61e0b7bb464fb39697c
--- /dev/null
+++ b/components/translate/core/browser/mock_translate_client.h
@@ -0,0 +1,67 @@
+// 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.
+
+#ifndef COMPONENTS_TRANSLATE_CORE_BROWSER_MOCK_TRANSLATE_CLIENT_H_
+#define COMPONENTS_TRANSLATE_CORE_BROWSER_MOCK_TRANSLATE_CLIENT_H_
+
+#include <memory>
+#include <string>
+
+#include "base/memory/ptr_util.h"
+#include "components/infobars/core/infobar.h"
+#include "components/translate/core/browser/translate_client.h"
+#include "components/translate/core/browser/translate_driver.h"
+#include "components/translate/core/browser/translate_prefs.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+namespace translate {
+
+extern const char* preferred_languages_prefs;

[groby-ooo-7-16, 2017/05/31 00:41:15]

We really shouldn't expose global constants from a mock object in a non-testing
namespace. (Ideally, we don't expose them at all.)

Note: I'm not sure how we can achieve this easily, so if Jon is OK, feel free to
skip that for this CL - but overall, these constants are showing up all over the
place. (And they're technically Chrome constants, not components constants)

[napper, 2017/05/31 01:16:37]

Yes this isn't very nice. Can you put the constants in the testing namespace?

[Leo, 2017/05/31 01:38:26]

Thanks for the concern and tips. I moved these to testing namespace. So they can
be used by all translate testing modules. 

+extern const char* accept_languages_prefs;
+
+namespace testing {
+
+class MockTranslateClient : public TranslateClient {
+ public:
+  MockTranslateClient(TranslateDriver* driver, PrefService* prefs);
+
+  ~MockTranslateClient() override;
+
+  TranslateDriver* GetTranslateDriver() override;
+
+  PrefService* GetPrefs() override;
+
+  std::unique_ptr<TranslatePrefs> GetTranslatePrefs() override;
+
+  MOCK_METHOD0(GetTranslateAcceptLanguages, TranslateAcceptLanguages*());
+  MOCK_CONST_METHOD0(GetInfobarIconID, int());
+
+#if !defined(USE_AURA)
+  MOCK_CONST_METHOD1(CreateInfoBarMock,
+                     infobars::InfoBar*(TranslateInfoBarDelegate*));
+  std::unique_ptr<infobars::InfoBar> CreateInfoBar(
+      std::unique_ptr<TranslateInfoBarDelegate> delegate) const {
+    return base::WrapUnique(CreateInfoBarMock(std::move(delegate).get()));

[napper, 2017/05/30 06:24:36]

This doesn't make sense to me:

std::move(delegate).get()

the move makes an xvalue, but then get() turns it into a raw pointer, which is
passed to CreateInfoBarMock. What is the purpose of the move()?

[groby-ooo-7-16, 2017/05/31 00:41:15]

I've done digging through history, and it seems that way from almost beginning
of time... Maybe weird behavioral differences between unique_ptr/scoped_ptr,
maybe an oversight in the original review. But yes, a delegate.get() should be
enough. 

[Leo, 2017/05/31 01:38:26]

Great to know the details.
Removed std::move()

+  }
+#endif
+
+  MOCK_METHOD5(ShowTranslateUI,
+               void(translate::TranslateStep,
+                    const std::string&,
+                    const std::string&,
+                    TranslateErrors::Type,
+                    bool));
+  MOCK_METHOD1(IsTranslatableURL, bool(const GURL&));
+  MOCK_METHOD1(ShowReportLanguageDetectionErrorUI, void(const GURL&));
+
+ private:
+  TranslateDriver* driver_;
+  PrefService* prefs_;
+};
+
+}  // namespace testing
+
+}  // namespace translate
+
+#endif  // COMPONENTS_TRANSLATE_CORE_BROWSER_MOCK_TRANSLATE_CLIENT_H_