Merge 131315 - Calling WebCore::SharedBuffer::append(data, 0) on a shared buffer when

Merge 131315 - Calling WebCore::SharedBuffer::append(data, 0) on a shared buffer when
its current position is at a segment boundary (4096) ends up adding an
unitialized segment (with uninitialized memory) to the SharedBuffer.
https://bugs.webkit.org/show_bug.cgi?id=99000

Reviewed by Adam Barth.

Source/WebCore:

* platform/SharedBuffer.cpp:
(WebCore::SharedBuffer::append):

LayoutTests:

* mhtml/shared_buffer_bug-expected.txt: Added.
* mhtml/shared_buffer_bug.mht: Added.


TBR=jcivelli@chromium.org
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=132676

[Jay Civelli, 2012-10-26 18:48:04]

lgtm