Miscellaneous cleanups.

stream_generator.h doesn't use anything from <string.h>. Replace
<string.h> with <stdint.h> for the intXXX_t typedefs.

Rename packet_buffer to packet_buffer_ to conform to the naming
convention of data members.

R=marpan@google.com, marpan@webrtc.org, phoglund@webrtc.org

BUG=none
TEST=none

Review URL: https://webrtc-codereview.appspot.com/51949004

Cr-Commit-Position: refs/heads/master@{#9387}
2 files changed