QuicSpdySession header size limit related cleanup.

This relands cr/257189926 which was reverted at cr/257303500 because in Chromium,
QuicChromiumClientSession::Initialize() called
set_max_uncompressed_header_bytes().  That call was since removed at
https://crrev.com/c/1693401.

Rename QuicSpdySession::SpdyFramerVisitor::set_max_uncompressed_header_bytes()
to set_max_header_list_size() to match the name of the QuicHeaderList method it
calls.

Inline set_max_uncompressed_header_bytes() and
set_max_decode_buffer_size_bytes() since they are used only once.

gfe-relnote: n/a, no functional change.
PiperOrigin-RevId: 259756568
Change-Id: I6c94e0d32ff418fdb8ccd14382bd9dd16fa82d39