Not creating ClientUsageTracker for unsupported storage type.

webkit/browser/fileapi/file_system_quota_client.cc

Index: webkit/browser/fileapi/file_system_quota_client.cc
diff --git a/webkit/browser/fileapi/file_system_quota_client.cc b/webkit/browser/fileapi/file_system_quota_client.cc
index 343a6e6ee5c7d90941c1a4da840990d1ad092b01..e9c0d18a9b9e863a30a1acfa58305f5c91cdc277 100644
--- a/webkit/browser/fileapi/file_system_quota_client.cc
+++ b/webkit/browser/fileapi/file_system_quota_client.cc
@@ -85,6 +85,7 @@ FileSystemQuotaClient::FileSystemQuotaClient(
     bool is_incognito)
     : file_system_context_(file_system_context),
       is_incognito_(is_incognito) {
+  file_system_context_->GetFileSystemTypes(&file_system_types_);
 }
 
 FileSystemQuotaClient::~FileSystemQuotaClient() {}
@@ -197,6 +198,13 @@ void FileSystemQuotaClient::DeleteOriginData(
       callback);
 }
 
+bool FileSystemQuotaClient::DoesSupport(quota::StorageType storage_type) const {
+  FileSystemType type = QuotaStorageTypeToFileSystemType(storage_type);
+  DCHECK(type != kFileSystemTypeUnknown);
+  return std::find(file_system_types_.begin(), file_system_types_.end(), type)
+      != file_system_types_.end();

[kinuko, 2013/08/29 10:21:42]

It looks we should just rather check if a given type is supported sandbox
filesystem type or not, which can be checked by:
file_system_context_->IsSandboxFileSystem(type)

[SeRya, 2013/08/29 12:14:14]

Good point. Only problem that IsSandboxFileSystem is implemented through
GetFileSystemBackend so it fails if <type> refers unregestered backend. I'm
fixing that.

+}
+
 base::SequencedTaskRunner* FileSystemQuotaClient::file_task_runner() const {
   return file_system_context_->default_file_task_runner();
 }