Revert 271602 "Implementation of leveldb-backed PrefStore."

Caused failure:

LevelDBPrefStoreTest.GetMutableValue (run #1):
[ RUN      ] LevelDBPrefStoreTest.GetMutableValue
Received signal 11 SEGV_MAPERR 000000000008
#0 0x00000345595e base::debug::StackTrace::StackTrace()
#1 0x000003455b78 base::debug::(anonymous namespace)::StackDumpSignalHandler()
#2 0x7f22d6faccb0 \u003Cunknown>
#3 0x000003473e6b base::JSONWriter::BuildJSONString()
#4 0x000003474aca base::JSONWriter::WriteWithOptions()
#5 0x0000028861d1 Serialize()
#6 0x000002888b6e LevelDBPrefStore::ReportValueChanged()
#7 0x0000016af06d LevelDBPrefStoreTest_GetMutableValue_Test::TestBody()

http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Tests%20%281%29/builds/43483/steps/unit_tests/logs/GetMutableValue

> Implementation of leveldb-backed PrefStore.
> 
> This is not hooked up yet, migration code from Json-backed stores is needed, among other things.
> 
> BUG=362814
> 
> Review URL: https://codereview.chromium.org/169323003

TBR=dgrogan@chromium.org

Review URL: https://codereview.chromium.org/290633013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@271611 0039d316-1c4b-4281-b951-d872f2087c98

base/prefs/json_pref_store.cc

@@ -330,11 +330,6 @@ void JsonPrefStore::OnFileRead(scoped_ptr<base::Value> value,
         // operation itself.
         NOTREACHED();
         break;
-      case PREF_READ_ERROR_LEVELDB_IO:
-      case PREF_READ_ERROR_LEVELDB_CORRUPTION_READ_ONLY:
-      case PREF_READ_ERROR_LEVELDB_CORRUPTION:
-        // These are specific to LevelDBPrefStore.
-        NOTREACHED();
       case PREF_READ_ERROR_MAX_ENUM:
         NOTREACHED();
         break;

base/prefs/persistent_pref_store.h

@@ -33,9 +33,6 @@ class BASE_PREFS_EXPORT PersistentPrefStore : public WriteablePrefStore {
     // Indicates that ReadPrefs() couldn't complete synchronously and is waiting
     // for an asynchronous task to complete first.
     PREF_READ_ERROR_ASYNCHRONOUS_TASK_INCOMPLETE = 10,
-    PREF_READ_ERROR_LEVELDB_IO = 11,
-    PREF_READ_ERROR_LEVELDB_CORRUPTION_READ_ONLY = 12,
-    PREF_READ_ERROR_LEVELDB_CORRUPTION = 13,
     PREF_READ_ERROR_MAX_ENUM
   };
 

chrome/browser/prefs/chrome_pref_service_factory.cc

@@ -313,8 +313,7 @@ void HandleReadError(PersistentPrefStore::PrefReadError error) {
     // an example problem that this can cause.
     // Do some diagnosis and try to avoid losing data.
     int message_id = 0;
-    if (error <= PersistentPrefStore::PREF_READ_ERROR_JSON_TYPE ||
-        error == PersistentPrefStore::PREF_READ_ERROR_LEVELDB_CORRUPTION) {
+    if (error <= PersistentPrefStore::PREF_READ_ERROR_JSON_TYPE) {
       message_id = IDS_PREFERENCES_CORRUPT_ERROR;
     } else if (error != PersistentPrefStore::PREF_READ_ERROR_NO_FILE) {
       message_id = IDS_PREFERENCES_UNREADABLE_ERROR;

chrome/browser/prefs/leveldb_pref_store.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_PREFS_LEVELDB_PREF_STORE_H_
-#define CHROME_BROWSER_PREFS_LEVELDB_PREF_STORE_H_
-
-#include <set>
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "base/files/file_path.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/message_loop/message_loop_proxy.h"
-#include "base/observer_list.h"
-#include "base/prefs/persistent_pref_store.h"
-#include "base/prefs/pref_value_map.h"
-#include "base/timer/timer.h"
-
-namespace base {
-class DictionaryValue;
-class SequencedTaskRunner;
-class Value;
-}
-
-namespace leveldb {
-class DB;
-}
-
-// A writable PrefStore implementation that is used for user preferences.
-class LevelDBPrefStore : public PersistentPrefStore {
- public:
-  // |sequenced_task_runner| is must be a shutdown-blocking task runner, ideally
-  // created by GetTaskRunnerForFile() method above.
-  LevelDBPrefStore(const base::FilePath& pref_filename,
-                   base::SequencedTaskRunner* sequenced_task_runner);
-
-  // PrefStore overrides:
-  virtual bool GetValue(const std::string& key,
-                        const base::Value** result) const OVERRIDE;
-  virtual void AddObserver(PrefStore::Observer* observer) OVERRIDE;
-  virtual void RemoveObserver(PrefStore::Observer* observer) OVERRIDE;
-  virtual bool HasObservers() const OVERRIDE;
-  virtual bool IsInitializationComplete() const OVERRIDE;
-
-  // PersistentPrefStore overrides:
-  virtual bool GetMutableValue(const std::string& key,
-                               base::Value** result) OVERRIDE;
-  // Takes ownership of value.
-  virtual void SetValue(const std::string& key, base::Value* value) OVERRIDE;
-  virtual void SetValueSilently(const std::string& key,
-                                base::Value* value) OVERRIDE;
-  virtual void RemoveValue(const std::string& key) OVERRIDE;
-  virtual bool ReadOnly() const OVERRIDE;
-  virtual PrefReadError GetReadError() const OVERRIDE;
-  virtual PrefReadError ReadPrefs() OVERRIDE;
-  virtual void ReadPrefsAsync(ReadErrorDelegate* error_delegate) OVERRIDE;
-  virtual void CommitPendingWrite() OVERRIDE;
-  virtual void ReportValueChanged(const std::string& key) OVERRIDE;
-
- private:
-  struct ReadingResults;
-  class FileThreadSerializer;
-
-  virtual ~LevelDBPrefStore();
-
-  static scoped_ptr<ReadingResults> DoReading(const base::FilePath& path);
-  static void OpenDB(const base::FilePath& path,
-                     ReadingResults* reading_results);
-  void OnStorageRead(scoped_ptr<ReadingResults> reading_results);
-
-  void PersistFromUIThread();
-  void RemoveFromUIThread(const std::string& key);
-  void ScheduleWrite();
-
-  void SetValueInternal(const std::string& key,
-                        base::Value* value,
-                        bool notify);
-  void NotifyObservers(const std::string& key);
-  void MarkForInsertion(const std::string& key, const std::string& value);
-  void MarkForDeletion(const std::string& key);
-
-  base::FilePath path_;
-
-  const scoped_refptr<base::SequencedTaskRunner> sequenced_task_runner_;
-  const scoped_refptr<base::SequencedTaskRunner> original_task_runner_;
-
-  PrefValueMap prefs_;
-
-  bool read_only_;
-
-  ObserverList<PrefStore::Observer, true> observers_;
-
-  scoped_ptr<ReadErrorDelegate> error_delegate_;
-
-  bool initialized_;
-  PrefReadError read_error_;
-
-  // This object is created on the UI thread right after preferences are loaded
-  // from disk. A message to delete it is sent to the FILE thread by
-  // ~LevelDBPrefStore.
-  scoped_ptr<FileThreadSerializer> serializer_;
-
-  // Changes are accumulated in |keys_to_delete_| and |keys_to_set_| and are
-  // stored in the database according to |timer_|.
-  std::set<std::string> keys_to_delete_;
-  std::map<std::string, std::string> keys_to_set_;
-  base::OneShotTimer<LevelDBPrefStore> timer_;
-
-  base::WeakPtrFactory<LevelDBPrefStore> weak_ptr_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(LevelDBPrefStore);
-};
-
-#endif  // CHROME_BROWSER_PREFS_LEVELDB_PREF_STORE_H_

chrome/chrome_browser.gypi

@@ -1549,8 +1549,6 @@
         'browser/prefs/incognito_mode_prefs.h',
         'browser/prefs/interceptable_pref_filter.cc',
         'browser/prefs/interceptable_pref_filter.h',
-        'browser/prefs/leveldb_pref_store.cc',
-        'browser/prefs/leveldb_pref_store.h',
         'browser/prefs/pref_hash_calculator.cc',
         'browser/prefs/pref_hash_calculator.h',
         'browser/prefs/pref_hash_filter.cc',

chrome/chrome_tests_unit.gypi

@@ -1154,7 +1154,6 @@
         'browser/prefs/chrome_pref_service_unittest.cc',
         'browser/prefs/command_line_pref_store_unittest.cc',
         'browser/prefs/incognito_mode_prefs_unittest.cc',
-        'browser/prefs/leveldb_pref_store_unittest.cc',
         'browser/prefs/pref_hash_calculator_unittest.cc',
         'browser/prefs/pref_hash_filter_unittest.cc',
         'browser/prefs/pref_hash_store_impl_unittest.cc',

chrome/test/data/prefs/corrupted_leveldb/CURRENT

-MANIFEST-000007
\ No newline at end of file

tools/metrics/histograms/histograms.xml

@@ -8989,14 +8989,6 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
-<histogram name="LevelDBPrefStore.ReadErrors" enum="LevelDBPrefStoreErrorCodes">
-  <owner>dgrogan@chromium.org</owner>
-  <summary>
-    Bitfield that indicates errors and recovery that occurred when opening a
-    LevelDB preferences database.
-  </summary>
-</histogram>
-
 <histogram name="LibraryLoader.NativeLibraryHack" enum="BooleanUsage">
   <owner>feng@chromium.org</owner>
   <summary>
@@ -37283,36 +37275,6 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <int value="20" label="GetChildren"/>
 </enum>
 
-<enum name="LevelDBPrefStoreErrorCodes" type="int">
-  <int value="1" label="OPENED"/>
-  <int value="5" label="REPAIRED | OPENED"/>
-  <int value="6" label="REPAIRED | DESTROYED"/>
-  <int value="7" label="REPAIRED | DESTROYED | OPENED"/>
-  <int value="12" label="REPAIRED | DESTROY_FAILED"/>
-  <int value="18" label="REPAIR_FAILED | DESTROYED"/>
-  <int value="19" label="REPAIR_FAILED | DESTROYED | OPENED"/>
-  <int value="24" label="REPAIR_FAILED | DESTROY_FAILED"/>
-  <int value="32" label="IO_ERROR"/>
-  <int value="36" label="REPAIRED | IO_ERROR"/>
-  <int value="38" label="REPAIRED | DESTROYED | IO_ERROR"/>
-  <int value="50" label="REPAIR_FAILED | DESTROYED | IO_ERROR"/>
-  <int value="65" label="OPENED | DATA_LOST"/>
-  <int value="69" label="REPAIRED | OPENED | DATA_LOST"/>
-  <int value="71" label="REPAIRED | DESTROYED | OPENED | DATA_LOST"/>
-  <int value="83" label="REPAIR_FAILED | DESTROYED | OPENED | DATA_LOST"/>
-  <int value="129" label="OPENED | ITER_NOT_OK"/>
-  <int value="133" label="REPAIRED | OPENED | ITER_NOT_OK"/>
-  <int value="135" label="REPAIRED | DESTROYED | OPENED | ITER_NOT_OK"/>
-  <int value="147" label="REPAIR_FAILED | DESTROYED | OPENED | ITER_NOT_OK"/>
-  <int value="193" label="OPENED | DATA_LOST | ITER_NOT_OK"/>
-  <int value="197" label="REPAIRED | OPENED | DATA_LOST | ITER_NOT_OK"/>
-  <int value="199"
-      label="REPAIRED | DESTROYED | OPENED | DATA_LOST | ITER_NOT_OK"/>
-  <int value="211"
-      label="REPAIR_FAILED | DESTROYED | OPENED | DATA_LOST | ITER_NOT_OK"/>
-  <int value="256" label="FILE_NOT_SPECIFIED"/>
-</enum>
-
 <enum name="LinkMonitorFailureType" type="int">
   <int value="0" label="Local MAC Address Not Found"/>
   <int value="1" label="Client Startup Failure"/>