Declare visibility on class property of MediaHandler

Change-Id: I95785992372a0f189b4543345ec1c040a4a7f7e4
Declare visibility on class properties of GIFMetadataExtractor

Change-Id: I4338caadaf69471084f3365ba9ce96f652d77374
Declare visibility on class property of FormatExif

Change-Id: Id5e7b3d29035946e44a0dd5939b9daec2e99aad0
Merge changes Id5e7b3d2,I4338caad,I95785992

* changes:
  Declare visibility on class property of FormatExif
  Declare visibility on class properties of GIFMetadataExtractor
  Declare visibility on class property of MediaHandler