Revert of Add most of the metadata-handling code for blobs. It's not quite all there, but

Revert of Add most of the metadata-handling code for blobs.  It's not quite all there, but (https://codereview.chromium.org/266333002/)

Reason for revert:
This seems to have broken some DB-related content_unittests http://build.chromium.org/p/chromium.win/builders/XP%20Tests%20%283%29/builds/27507, the stdio contains a couple of the following backtraces:
[2092:3704:0512/235433:3686281:ERROR:indexed_db_backing_store.cc(376)] IndexedDB Write Error: SET_UP_METADATA
Backtrace:
	(No symbol) [0x00B727AA]
	(No symbol) [0x00730997]
	(No symbol) [0x00D401E9]
	(No symbol) [0x00D4036E]
	(No symbol) [0x00D4094E]
	(No symbol) [0x00D40689]
	(No symbol) [0x00D1B0B8]
	(No symbol) [0x00D1ADE7]
	(No symbol) [0x00A6322D]
	(No symbol) [0x022D0761]
	RegisterWaitForInputIdle [0x7C816037+73]

Original issue's description:
> Add most of the metadata-handling code for blobs.  It's not quite all there, but
> this is the biggest chunk I can pull out vaguely cleanly.  It does contain a
> couple of fake calls to keep the compiler happy.
> This CL also makes SetUpMetadata a member in order to ease testing in a later CL.
> 
> This depends on https://codereview.chromium.org/261843004/.
> 
> BUG=108012
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=270016

TBR=cmumford@chromium.org,jsbell@chromium.org,ericu@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=108012

[vabr (Chromium), 2014-05-13 07:02:55]

Created Revert of Add most of the metadata-handling code for blobs.  It's not
quite all there, but

[commit-bot: I haz the power, 2014-05-13 07:03:05]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/vabr@chromium.org/288523002/1

[commit-bot: I haz the power, 2014-05-13 07:03:53]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-05-13 07:03:54]

Failed to apply patch for
content/browser/indexed_db/indexed_db_backing_store.cc:
While running patch -p1 --forward --force --no-backup-if-mismatch;
  patching file content/browser/indexed_db/indexed_db_backing_store.cc
  Hunk #1 FAILED at 128.
  Hunk #2 FAILED at 306.
  Hunk #3 FAILED at 344.
  Hunk #4 FAILED at 370.
  Hunk #5 FAILED at 383.
  Hunk #6 FAILED at 414.
  Hunk #7 FAILED at 496.
  Hunk #8 FAILED at 637.
  Hunk #9 FAILED at 713.
  Hunk #10 FAILED at 763.
  Hunk #11 FAILED at 1049.
  Hunk #12 FAILED at 1121.
  Hunk #13 FAILED at 1216.
  Hunk #14 FAILED at 1294.
  Hunk #15 FAILED at 1332.
  Hunk #16 FAILED at 1396.
  Hunk #17 FAILED at 1427.
  Hunk #18 FAILED at 1739.
  Hunk #19 FAILED at 1813.
  Hunk #20 FAILED at 1909.
  Hunk #21 FAILED at 2512.
  Hunk #22 FAILED at 2899.
  Hunk #23 FAILED at 2915.
  Hunk #24 FAILED at 3111.
  Hunk #25 FAILED at 3175.
  Hunk #26 FAILED at 3231.
  Hunk #27 FAILED at 3243.
  Hunk #28 FAILED at 3323.
  Hunk #29 FAILED at 3346.
  Hunk #30 FAILED at 3356.
  Hunk #31 FAILED at 3429.
  Hunk #32 FAILED at 3437.
  Hunk #33 FAILED at 3460.
  Hunk #34 FAILED at 3634.
  Hunk #35 FAILED at 3661.
  Hunk #36 FAILED at 3691.
  Hunk #37 FAILED at 3719.
  37 out of 37 hunks FAILED -- saving rejects to file
content/browser/indexed_db/indexed_db_backing_store.cc.rej

Patch:       content/browser/indexed_db/indexed_db_backing_store.cc
Index: content/browser/indexed_db/indexed_db_backing_store.cc
diff --git a/content/browser/indexed_db/indexed_db_backing_store.cc
b/content/browser/indexed_db/indexed_db_backing_store.cc
index
1cf95619fee41503306b7e72b8b3c8488125eda4..36e514ad2afef6fd7054cb7c13a3887dfad06ce9
100644
--- a/content/browser/indexed_db/indexed_db_backing_store.cc
+++ b/content/browser/indexed_db/indexed_db_backing_store.cc
@@ -128,8 +128,6 @@
   CLEAR_OBJECT_STORE,
   READ_BLOB_JOURNAL,
   DECODE_BLOB_JOURNAL,
-  GET_BLOB_KEY_GENERATOR_CURRENT_NUMBER,
-  GET_BLOB_INFO_FOR_RECORD,
   INTERNAL_ERROR_MAX,
 };
 
@@ -306,8 +304,7 @@
 // 0 - Initial version.
 // 1 - Adds UserIntVersion to DatabaseMetaData.
 // 2 - Adds DataVersion to to global metadata.
-// 3 - Adds metadata needed for blob support.
-static const int64 kLatestKnownSchemaVersion = 3;
+static const int64 kLatestKnownSchemaVersion = 2;
 WARN_UNUSED_RESULT static bool IsSchemaKnown(LevelDBDatabase* db, bool* known)
{
   int64 db_schema_version = 0;
   bool found = false;
@@ -344,16 +341,15 @@
   return true;
 }
 
-// TODO(ericu): Move this down into the member section of this file.  I'm
-// leaving it here for this CL as it's easier to see the diffs in place.
-WARN_UNUSED_RESULT bool IndexedDBBackingStore::SetUpMetadata() {
+WARN_UNUSED_RESULT static bool SetUpMetadata(
+    LevelDBDatabase* db,
+    const std::string& origin_identifier) {
   const uint32 latest_known_data_version =
       blink::kSerializedScriptValueVersion;
   const std::string schema_version_key = SchemaVersionKey::Encode();
   const std::string data_version_key = DataVersionKey::Encode();
 
-  scoped_refptr<LevelDBTransaction> transaction =
-      new LevelDBTransaction(db_.get());
+  scoped_refptr<LevelDBTransaction> transaction = new LevelDBTransaction(db);
 
   int64 db_schema_version = 0;
   int64 db_data_version = 0;
@@ -370,12 +366,6 @@
     PutInt(transaction.get(), schema_version_key, db_schema_version);
     db_data_version = latest_known_data_version;
     PutInt(transaction.get(), data_version_key, db_data_version);
-    // If a blob directory already exists for this database, blow it away. 
It's
-    // leftover from a partially-purged previous generation of data.
-    if (!base::DeleteFile(blob_path_, true)) {
-      INTERNAL_WRITE_ERROR_UNTESTED(SET_UP_METADATA);
-      return false;
-    }
   } else {
     // Upgrade old backing store.
     DCHECK_LE(db_schema_version, kLatestKnownSchemaVersion);
@@ -383,10 +373,10 @@
       db_schema_version = 1;
       PutInt(transaction.get(), schema_version_key, db_schema_version);
       const std::string start_key =
-          DatabaseNameKey::EncodeMinKeyForOrigin(origin_identifier_);
+          DatabaseNameKey::EncodeMinKeyForOrigin(origin_identifier);
       const std::string stop_key =
-          DatabaseNameKey::EncodeStopKeyForOrigin(origin_identifier_);
-      scoped_ptr<LevelDBIterator> it = db_->CreateIterator();
+          DatabaseNameKey::EncodeStopKeyForOrigin(origin_identifier);
+      scoped_ptr<LevelDBIterator> it = db->CreateIterator();
       for (s = it->Seek(start_key);
            s.ok() && it->IsValid() && CompareKeys(it->Key(), stop_key) < 0;
            s = it->Next()) {
@@ -414,13 +404,6 @@
       db_data_version = blink::kSerializedScriptValueVersion;
       PutInt(transaction.get(), data_version_key, db_data_version);
     }
-    if (db_schema_version < 3) {
-      db_schema_version = 3;
-      if (!base::DeleteFile(blob_path_, true)) {
-        INTERNAL_WRITE_ERROR_UNTESTED(SET_UP_METADATA);
-        return false;
-      }
-    }
   }
 
   if (!s.ok()) {
@@ -496,55 +479,6 @@
     return LevelDBDatabase::Destroy(file_name);
   }
 };
-
-static bool GetBlobKeyGeneratorCurrentNumber(
-    LevelDBTransaction* leveldb_transaction,
-    int64 database_id,
-    int64* blob_key_generator_current_number) {
-  const std::string key_gen_key = DatabaseMetaDataKey::Encode(
-      database_id, DatabaseMetaDataKey::BLOB_KEY_GENERATOR_CURRENT_NUMBER);
-
-  // Default to initial number if not found.
-  int64 cur_number = DatabaseMetaDataKey::kBlobKeyGeneratorInitialNumber;
-  std::string data;
-
-  bool found = false;
-  bool ok = leveldb_transaction->Get(key_gen_key, &data, &found).ok();
-  if (!ok) {
-    INTERNAL_READ_ERROR_UNTESTED(GET_BLOB_KEY_GENERATOR_CURRENT_NUMBER);
-    return false;
-  }
-  if (found) {
-    StringPiece slice(data);
-    if (!DecodeVarInt(&slice, &cur_number) || !slice.empty() ||
-        !DatabaseMetaDataKey::IsValidBlobKey(cur_number)) {
-      INTERNAL_READ_ERROR_UNTESTED(GET_BLOB_KEY_GENERATOR_CURRENT_NUMBER);
-      return false;
-    }
-  }
-  *blob_key_generator_current_number = cur_number;
-  return true;
-}
-
-static bool UpdateBlobKeyGeneratorCurrentNumber(
-    LevelDBTransaction* leveldb_transaction,
-    int64 database_id,
-    int64 blob_key_generator_current_number) {
-#ifndef NDEBUG
-  int64 old_number;
-  if (!GetBlobKeyGeneratorCurrentNumber(
-          leveldb_transaction, database_id, &old_number))
-    return false;
-  DCHECK_LT(old_number, blob_key_generator_current_number);
-#endif
-  DCHECK(
-      DatabaseMetaDataKey::IsValidBlobKey(blob_key_generator_current_number));
-  const std::string key = DatabaseMetaDataKey::Encode(
-      database_id, DatabaseMetaDataKey::BLOB_KEY_GENERATOR_CURRENT_NUMBER);
-
-  PutVarInt(leveldb_transaction, key, blob_key_generator_current_number);
-  return true;
-}
 
 // TODO(ericu): Error recovery. If we persistently can't read the
 // blob journal, the safe thing to do is to clear it and leak the blobs,
@@ -637,64 +571,6 @@
   EncodeBlobJournal(journal, &data);
   leveldb_transaction->Put(key, &data);
   return leveldb::Status::OK();
-}
-
-// Blob Data is encoded as a series of:
-//   { is_file [bool], key [int64 as varInt],
-//     type [string-with-length, may be empty],
-//     (for Blobs only) size [int64 as varInt]
-//     (for Files only) fileName [string-with-length]
-//   }
-// There is no length field; just read until you run out of data.
-static std::string EncodeBlobData(
-    const std::vector<IndexedDBBlobInfo*>& blob_info) {
-  std::string ret;
-  std::vector<IndexedDBBlobInfo*>::const_iterator iter;
-  for (iter = blob_info.begin(); iter != blob_info.end(); ++iter) {
-    const IndexedDBBlobInfo& info = **iter;
-    EncodeBool(info.is_file(), &ret);
-    EncodeVarInt(info.key(), &ret);
-    EncodeStringWithLength(info.type(), &ret);
-    if (info.is_file())
-      EncodeStringWithLength(info.file_name(), &ret);
-    else
-      EncodeVarInt(info.size(), &ret);
-  }
-  return ret;
-}
-
-static bool DecodeBlobData(const std::string& data,
-                           std::vector<IndexedDBBlobInfo>* output) {
-  std::vector<IndexedDBBlobInfo> ret;
-  output->clear();
-  StringPiece slice(data);
-  while (!slice.empty()) {
-    bool is_file;
-    int64 key;
-    base::string16 type;
-    int64 size;
-    base::string16 file_name;
-
-    if (!DecodeBool(&slice, &is_file))
-      return false;
-    if (!DecodeVarInt(&slice, &key) ||
-        !DatabaseMetaDataKey::IsValidBlobKey(key))
-      return false;
-    if (!DecodeStringWithLength(&slice, &type))
-      return false;
-    if (is_file) {
-      if (!DecodeStringWithLength(&slice, &file_name))
-        return false;
-      ret.push_back(IndexedDBBlobInfo(key, type, file_name));
-    } else {
-      if (!DecodeVarInt(&slice, &size) || size < 0)
-        return false;
-      ret.push_back(IndexedDBBlobInfo(type, static_cast<uint64>(size), key));
-    }
-  }
-  output->swap(ret);
-
-  return true;
 }
 
 IndexedDBBackingStore::IndexedDBBackingStore(
@@ -713,8 +589,7 @@
       task_runner_(task_runner),
       db_(db.Pass()),
       comparator_(comparator.Pass()),
-      active_blob_registry_(this) {
-}
+      active_blob_registry_(this) {}
 
 IndexedDBBackingStore::~IndexedDBBackingStore() {
   if (!blob_path_.empty() && !child_process_ids_granted_.empty()) {
@@ -763,7 +638,6 @@
   INDEXED_DB_BACKING_STORE_OPEN_ORIGIN_TOO_LONG,
   INDEXED_DB_BACKING_STORE_OPEN_NO_RECOVERY,
   INDEXED_DB_BACKING_STORE_OPEN_FAILED_PRIOR_CORRUPTION,
-  INDEXED_DB_BACKING_STORE_OPEN_FAILED_CLEANUP_JOURNAL_ERROR,
   INDEXED_DB_BACKING_STORE_OPEN_MAX,
 };
 
@@ -1049,22 +923,13 @@
     return scoped_refptr<IndexedDBBackingStore>();
   }
 
-  scoped_refptr<IndexedDBBackingStore> backing_store =
-      Create(indexed_db_factory,
-             origin_url,
-             blob_path,
-             request_context,
-             db.Pass(),
-             comparator.Pass(),
-             task_runner);
-
-  if (clean_journal && backing_store &&
-      !bac…
(message too large)

[vabr (Chromium), 2014-05-13 08:56:19]

I see this was reverted by https://codereview.chromium.org/281623004. Thanks
ericu@ for a prompt action! :)