Account for HTTP/2 padding in receive windows.

Account for HTTP/2 padding in receive windows.

Account for pad length field and padding in HTTP/2 session and stream receive
windows, because they are part of the payload.

This CL introduces a new method OnStreamPadding, calls it when processing
padding, implements it to update the receive windows appropriately (both
for session and for stream), and adds trivial implementations for all
subclasses.

This CL also lands internal changes 88830613 and 89327497 by bnc
and 89034703 by mpw.

BUG=353012
Committed: https://crrev.com/43cdf67d11deda1a4ccca51e44a5183bda93b245
Cr-Commit-Position: refs/heads/master@{#322137}

[Bence, 2015-02-25 18:52:12]

bnc@chromium.org changed reviewers:
+ rch@chromium.org

[Bence, 2015-02-25 18:52:12]

Ryan: PTAL.  Thanks.

[Ryan Hamilton, 2015-02-25 21:59:15]

I think this is basically fine, but I'm not in love with the SpdyFramer's
interaction with the visitor.

https://codereview.chromium.org/959743002/diff/20001/net/spdy/spdy_framer.cc
File net/spdy/spdy_framer.cc (right):

https://codereview.chromium.org/959743002/diff/20001/net/spdy/spdy_framer.cc#...
net/spdy/spdy_framer.cc:2173: kPadLengthFieldSize, false);
Should this change land internally first? In any case, I'm not in love with this
approach. I think I'd prefer either:
1) and explicit OnStreamPadding() or
2) and extra size_t num_padding_bytes argument to OnStreamFrameData()

[Bence, 2015-03-24 15:54:40]

Ryan, PTAL.  Thanks.

[Ryan Hamilton, 2015-03-24 19:26:14]

lgtm

[Bence, 2015-03-25 10:59:40]

The CQ bit was checked by bnc@chromium.org

[commit-bot: I haz the power, 2015-03-25 11:00:00]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/959743002/100001

[commit-bot: I haz the power, 2015-03-25 11:33:51]

Committed patchset #6 (id:100001)

[commit-bot: I haz the power, 2015-03-25 11:34:24]

Patchset 6 (id:??) landed as
https://crrev.com/43cdf67d11deda1a4ccca51e44a5183bda93b245
Cr-Commit-Position: refs/heads/master@{#322137}