libwebp: fix some int <-> size_t mix for buffer sizes

libwebp: fix some int <-> size_t mix for buffer sizes

This is to prevent overflow to negative.
(althought we're testing total_size = (size_t)total_size)

Patch by skal@google.com.

BUG=136894
TEST=none

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=146440

[scherkus (not reviewing), 2012-07-12 17:44:25]

Will wait for skal@ to give the final l-g-t-m after he's done testing

[jzern, 2012-07-12 20:12:29]

https://chromiumcodereview.appspot.com/10690171/diff/1/third_party/libwebp/we...
File third_party/libwebp/webp/decode.h (right):

https://chromiumcodereview.appspot.com/10690171/diff/1/third_party/libwebp/we...
third_party/libwebp/webp/decode.h:125: int size;         // total size of the
*rgba buffer.
missed one. relevant upstream change is v0.1.3-208-g9b3d1f3

[Peter Kasting, 2012-07-12 20:33:22]

Random drive-by: In Chrome I'd call out the use of C-style casts and ask for C++
ones... don't know the rules here.

[scherkus (not reviewing), 2012-07-12 21:16:51]

PTAL jzern/skal/etc that this is the fix we want to land

pkasting: I guess c-casts are acceptable in libwebp :)

[scherkus (not reviewing), 2012-07-12 21:17:28]

actually libwebp _is_ C code -- so there you have it!

[skal, 2012-07-12 21:21:38]

LGTM

thanks Andrew for doing the lifting!

Peter: it's even worse than that: libwebp is C89 :)

[jzern, 2012-07-12 21:30:47]

lgtm