Revert 160644 "WEBPImageDecoder: Fix for ASSERTION FAILED: width..."

Reverting because the Blink rolls are failing the CQ on
android_dbg_triggered_tests on webkit_unit_tests for
AnimatedWebPTests.truncatedInBetweenFrame

> WEBPImageDecoder: Fix for ASSERTION FAILED: width == frameRect.width()
> 
> If all data of a frame is received, but WebPIUpdate returns VP8_STATUS_SUSPENDED, then it's an invalid image.
> 
> BUG=310259
> R=pkasting@chromium.org
> 
> Review URL: https://codereview.chromium.org/36363002

TBR=urvang@google.com

Review URL: https://codereview.chromium.org/47373002

git-svn-id: svn://svn.chromium.org/blink/trunk@160666 bbb929c8-8fbe-4397-9dbb-9b2b20218538