[SystemInfo API] Rewrite storage info provider using storage monitor impl

chrome/browser/storage_monitor/storage_monitor_chromeos.cc

Index: chrome/browser/storage_monitor/storage_monitor_chromeos.cc
diff --git a/chrome/browser/storage_monitor/storage_monitor_chromeos.cc b/chrome/browser/storage_monitor/storage_monitor_chromeos.cc
index 5501d1dad84ff5815e63e3d583d430bb59a37211..91c82fa594b583f6f721d233961eb32d5798c1ab 100644
--- a/chrome/browser/storage_monitor/storage_monitor_chromeos.cc
+++ b/chrome/browser/storage_monitor/storage_monitor_chromeos.cc
@@ -282,6 +282,18 @@ StorageMonitorCros::media_transfer_protocol_manager() {
   return media_transfer_protocol_manager_.get();
 }
 
+std::vector<chrome::StorageInfo>
+StorageMonitorCros::GetAllAvailableStorages() const {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  std::vector<chrome::StorageInfo> results;
+
+  for (MountMap::const_iterator it = mount_map_.begin();
+       it != mount_map_.end(); ++it)
+    results.push_back(it->second);
+
+  return results;
+}
+
 void StorageMonitorCros::AddMountedPath(
     const disks::DiskMountManager::MountPointInfo& mount_info, bool has_dcim) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));