Make WebP decoding independent of stream length.

Make WebP decoding independent of stream length.

There's a case in Android, when the SkStream passed to WebP decoder may have
incorrect length (stream->getLength()). This is observed, if the App decodes
an image (size > 80KB) using: 'ParcelFileDescriptor --> BitmapFactory.decodeStream()'.
This CL updates the WebP incremental decoding loop to not rely on stream->getLength().

R=scroggo@google.com, vikasa@google.com

Committed: https://code.google.com/p/skia/source/detail?r=10651

[djsollen, 2013-08-08 12:43:26]

This moves a CL upstream that was originally committed to Android.

[vikasa, 2013-08-08 16:57:29]

lgtm

[scroggo, 2013-08-08 18:44:24]

lgtm besides some style guide violations.

https://codereview.chromium.org/22672003/diff/1/src/images/SkImageDecoder_lib...
File src/images/SkImageDecoder_libwebp.cpp (right):

https://codereview.chromium.org/22672003/diff/1/src/images/SkImageDecoder_lib...
src/images/SkImageDecoder_libwebp.cpp:209: const uint32_t bytes_to_read =
WEBP_IDECODE_BUFFER_SZ;
bytesToRead

https://codereview.chromium.org/22672003/diff/1/src/images/SkImageDecoder_lib...
src/images/SkImageDecoder_libwebp.cpp:210: const size_t bytes_read =
stream->read(input, bytes_to_read);
bytesRead

https://codereview.chromium.org/22672003/diff/1/src/images/SkImageDecoder_lib...
src/images/SkImageDecoder_libwebp.cpp:211: if (bytes_read == 0) {
if (0 == bytesRead)

[djsollen, 2013-08-09 12:33:35]

Committed patchset #2 manually as r10651 (presubmit successful).

[djsollen, 2013-08-09 15:19:02]

On 2013/08/09 12:33:35, djsollen wrote:
> Committed patchset #2 manually as r10651 (presubmit successful).

This change had to be reverted due to failures on Windows.  All the other
platforms built and ran successfully.

http://108.170.217.252:10117/builders/Test-Win7-ShuttleA-HD2000-x86-Debug/bui...

We've filed a bug (https://code.google.com/p/skia/issues/detail?id=1495) to
track the issue.