Return number of values deleted by IDBObjectStore.delete(range)

content/browser/indexed_db/indexed_db_database.cc

Index: content/browser/indexed_db/indexed_db_database.cc
diff --git a/content/browser/indexed_db/indexed_db_database.cc b/content/browser/indexed_db/indexed_db_database.cc
index c686ae87ad3aaa4a86d13e948f644c1f0c8265ba..09b27422e7c6e28a6e3701a0e629ed876b8ccb2e 100644
--- a/content/browser/indexed_db/indexed_db_database.cc
+++ b/content/browser/indexed_db/indexed_db_database.cc
@@ -12,11 +12,13 @@
 #include <utility>
 
 #include "base/auto_reset.h"
+#include "base/command_line.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/scoped_vector.h"
 #include "base/metrics/histogram_macros.h"
+#include "base/numerics/safe_conversions.h"
 #include "base/stl_util.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
@@ -35,6 +37,7 @@
 #include "content/common/indexed_db/indexed_db_constants.h"
 #include "content/common/indexed_db/indexed_db_key_path.h"
 #include "content/common/indexed_db/indexed_db_key_range.h"
+#include "content/public/common/content_switches.h"
 #include "storage/browser/blob/blob_data_handle.h"
 #include "third_party/WebKit/public/platform/modules/indexeddb/WebIDBDatabaseException.h"
 #include "third_party/leveldatabase/env_chromium.h"
@@ -157,7 +160,10 @@ IndexedDBDatabase::IndexedDBDatabase(const base::string16& name,
                 IndexedDBDatabaseMetadata::NO_VERSION,
                 kInvalidId),
       identifier_(unique_identifier),
-      factory_(factory) {
+      factory_(factory),
+      experimental_web_platform_features_enabled_(
+          base::CommandLine::ForCurrentProcess()->HasSwitch(
+              switches::kEnableExperimentalWebPlatformFeatures)) {
   DCHECK(factory != NULL);
 }
 
@@ -1410,13 +1416,12 @@ void IndexedDBDatabase::DeleteRangeOperation(
     std::unique_ptr<IndexedDBKeyRange> key_range,
     scoped_refptr<IndexedDBCallbacks> callbacks,
     IndexedDBTransaction* transaction) {
-  IDB_TRACE1(
-      "IndexedDBDatabase::DeleteRangeOperation", "txn.id", transaction->id());
+  IDB_TRACE1("IndexedDBDatabase::DeleteRangeOperation", "txn.id",
+             transaction->id());
+  size_t delete_count = 0;
   leveldb::Status s =
-      backing_store_->DeleteRange(transaction->BackingStoreTransaction(),
-                                  id(),
-                                  object_store_id,
-                                  *key_range);
+      backing_store_->DeleteRange(transaction->BackingStoreTransaction(), id(),
+                                  object_store_id, *key_range, &delete_count);
   if (!s.ok()) {
     base::string16 error_string =
         ASCIIToUTF16("Internal error deleting data in range");
@@ -1428,7 +1433,10 @@ void IndexedDBDatabase::DeleteRangeOperation(
     }
     return;
   }
-  callbacks->OnSuccess();
+  if (experimental_web_platform_features_enabled_)

[dmurph, 2016/05/26 18:35:27]

Please add brackets to both here.

Our style guide is a little weird. Basically, removing braces is ok IFF
* the next statement fits on one line, and
* there is no 'else'

https://google.github.io/styleguide/cppguide.html#Conditionals

+    callbacks->OnSuccess(base::checked_cast<int64_t>(delete_count));
+  else
+    callbacks->OnSuccess();
 }
 
 void IndexedDBDatabase::Clear(int64_t transaction_id,