Bump Crosswalk to 34.0.1847.45

This includes build fixes deu to renamings in Chromium, as well as the
following squashed commits:

Author: Thiago Marcos P. Santos <thiago.santos@intel.com>:
- [SysApps] Fix component build
- [SysApps] Update StorageMonitor usage : Now we need
  to ::Create() the instance explicitly before using.

Author: Shiliu Wang <shiliu.wang@intel.com>:
- [Android] Register JNI entries while libxwalkcore.so is loaded

  Upstream moves RegisterLibraryLoaderEntryHook from content
  to base, but the real registration is still done at
  content::LibraryLoaded, which is missed in xwalk.

  Add the callback back to fix the issue.