Extension Settings API: make it so that when changes received from Sync fail to

chrome/browser/extensions/settings/testing_settings_storage.cc

Index: chrome/browser/extensions/settings/testing_settings_storage.cc
diff --git a/chrome/browser/extensions/settings/in_memory_settings_storage.cc b/chrome/browser/extensions/settings/testing_settings_storage.cc
similarity index 60%
rename from chrome/browser/extensions/settings/in_memory_settings_storage.cc
rename to chrome/browser/extensions/settings/testing_settings_storage.cc
index d017a692d598a9dbb6c4ca5967b862e081412d85..7b256ec2157095ae3b94d9066124c8cb1bad7dcf 100644
--- a/chrome/browser/extensions/settings/in_memory_settings_storage.cc
+++ b/chrome/browser/extensions/settings/testing_settings_storage.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/browser/extensions/settings/in_memory_settings_storage.h"
+#include "chrome/browser/extensions/settings/testing_settings_storage.h"
 
 #include "base/logging.h"
 
@@ -10,6 +10,16 @@ namespace extensions {
 
 namespace {
 
+const char* kGenericErrorMessage = "TestingSettingsStorage configured to error";
+
+SettingsStorage::ReadResult ReadResultError() {
+  return SettingsStorage::ReadResult(kGenericErrorMessage);
+}
+
+SettingsStorage::WriteResult WriteResultError() {
+  return SettingsStorage::WriteResult(kGenericErrorMessage);
+}
+
 std::vector<std::string> CreateVector(const std::string& string) {
   std::vector<std::string> strings;
   strings.push_back(string);
@@ -18,13 +28,26 @@ std::vector<std::string> CreateVector(const std::string& string) {
 
 }  // namespace
 
-SettingsStorage::ReadResult InMemorySettingsStorage::Get(
+TestingSettingsStorage::TestingSettingsStorage()
+    : fail_all_requests_(false) {}
+
+TestingSettingsStorage::~TestingSettingsStorage() {}
+
+void TestingSettingsStorage::SetFailAllRequests(bool fail_all_requests) {
+  fail_all_requests_ = fail_all_requests;
+}
+
+SettingsStorage::ReadResult TestingSettingsStorage::Get(
     const std::string& key) {
   return Get(CreateVector(key));
 }
 
-SettingsStorage::ReadResult InMemorySettingsStorage::Get(
+SettingsStorage::ReadResult TestingSettingsStorage::Get(
     const std::vector<std::string>& keys) {
+  if (fail_all_requests_) {
+    return ReadResultError();
+  }
+
   DictionaryValue* settings = new DictionaryValue();
   for (std::vector<std::string>::const_iterator it = keys.begin();
       it != keys.end(); ++it) {
@@ -36,21 +59,27 @@ SettingsStorage::ReadResult InMemorySettingsStorage::Get(
   return ReadResult(settings);
 }
 
-SettingsStorage::ReadResult InMemorySettingsStorage::Get() {
+SettingsStorage::ReadResult TestingSettingsStorage::Get() {
+  if (fail_all_requests_) {
+    return ReadResultError();
+  }
   return ReadResult(storage_.DeepCopy());
 }
 
-SettingsStorage::WriteResult InMemorySettingsStorage::Set(
+SettingsStorage::WriteResult TestingSettingsStorage::Set(
     const std::string& key, const Value& value) {
   DictionaryValue settings;
   settings.SetWithoutPathExpansion(key, value.DeepCopy());
   return Set(settings);
 }
 
-SettingsStorage::WriteResult InMemorySettingsStorage::Set(
+SettingsStorage::WriteResult TestingSettingsStorage::Set(
     const DictionaryValue& settings) {
-  scoped_ptr<SettingChangeList> changes(
-      new SettingChangeList());
+  if (fail_all_requests_) {
+    return WriteResultError();
+  }
+
+  scoped_ptr<SettingChangeList> changes(new SettingChangeList());
   for (DictionaryValue::Iterator it(settings); it.HasNext(); it.Advance()) {
     Value* old_value = NULL;
     storage_.GetWithoutPathExpansion(it.key(), &old_value);
@@ -66,13 +95,17 @@ SettingsStorage::WriteResult InMemorySettingsStorage::Set(
   return WriteResult(changes.release());
 }
 
-SettingsStorage::WriteResult InMemorySettingsStorage::Remove(
+SettingsStorage::WriteResult TestingSettingsStorage::Remove(
     const std::string& key) {
   return Remove(CreateVector(key));
 }
 
-SettingsStorage::WriteResult InMemorySettingsStorage::Remove(
+SettingsStorage::WriteResult TestingSettingsStorage::Remove(
     const std::vector<std::string>& keys) {
+  if (fail_all_requests_) {
+    return WriteResultError();
+  }
+
   scoped_ptr<SettingChangeList> changes(
       new SettingChangeList());
   for (std::vector<std::string>::const_iterator it = keys.begin();
@@ -85,8 +118,11 @@ SettingsStorage::WriteResult InMemorySettingsStorage::Remove(
   return WriteResult(changes.release());
 }
 
-SettingsStorage::WriteResult
-InMemorySettingsStorage::Clear() {
+SettingsStorage::WriteResult TestingSettingsStorage::Clear() {
+  if (fail_all_requests_) {
+    return WriteResultError();
+  }
+
   std::vector<std::string> keys;
   for (DictionaryValue::Iterator it(storage_); it.HasNext(); it.Advance()) {
     keys.push_back(it.key());