libstagefright: set actual stride info for SW encoder input port

This fixes encoding flexible YUV content using SW encoders.
Also skip setting input color format if it is flexible YUV, as it
has already been translated to a color format supported by the codec.

Bug: 18124320
Change-Id: I423782936986f4d6cf65ea9ef89ae77a92e30140
4 files changed