Make ChunkDemuxer::SetTimestampOffset take a TimeDelta instead of double

Make ChunkDemuxer::SetTimestampOffset take a TimeDelta instead of double

ChunkDemuxerTest.TestDurationChangeTimestampOffset tickled a precision error in 
32-bit linux due to the division by InSecondsF(). This situation can be avoided
by moving the double -> TimeDelta conversion into WebMediaPlayerImpl so that
ChunkDemuxer can compute all times in terms of TimeDeltas.

BUG=NONE

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=151601

[Ami GONE FROM CHROMIUM, 2012-08-14 00:05:18]

https://chromiumcodereview.appspot.com/10823300/diff/1/media/filters/chunk_de...
File media/filters/chunk_demuxer_unittest.cc (right):

https://chromiumcodereview.appspot.com/10823300/diff/1/media/filters/chunk_de...
media/filters/chunk_demuxer_unittest.cc:2332: kDefaultDuration().InSecondsF()));
Per offline convo: IWBN if ChunkDemuxer dealt only in TimeDeltas, and WMPI hid
the |double seconds| specified in the Media Source API.  As a side-effect, this
test would stop dividing, and hopefully be independent of the vagaries of 80-bit
register math on x86.

[vrk (LEFT CHROMIUM), 2012-08-14 01:06:43]

Thanks Ami, this is definitely the better way to go. PTAL.

[Ami GONE FROM CHROMIUM, 2012-08-14 02:00:44]

LGTM

https://chromiumcodereview.appspot.com/10823300/diff/3/media/filters/chunk_de...
File media/filters/chunk_demuxer.h (right):

https://chromiumcodereview.appspot.com/10823300/diff/3/media/filters/chunk_de...
media/filters/chunk_demuxer.h:77: // Sets a time |offset| in seconds to be
applied to subsequent buffers
drop "in seconds"

https://chromiumcodereview.appspot.com/10823300/diff/3/webkit/media/webmediap...
File webkit/media/webmediaplayer_impl.cc (right):

https://chromiumcodereview.appspot.com/10823300/diff/3/webkit/media/webmediap...
webkit/media/webmediaplayer_impl.cc:691: offset *
base::Time::kMicrosecondsPerSecond);
I suspect this wants to use webmediaplayer_util.h, but that can be another CL.

[vrk (LEFT CHROMIUM), 2012-08-14 23:30:25]

https://chromiumcodereview.appspot.com/10823300/diff/3/media/filters/chunk_de...
File media/filters/chunk_demuxer.h (right):

https://chromiumcodereview.appspot.com/10823300/diff/3/media/filters/chunk_de...
media/filters/chunk_demuxer.h:77: // Sets a time |offset| in seconds to be
applied to subsequent buffers
On 2012/08/14 02:00:44, Ami Fischman wrote:
> drop "in seconds"

Done.

https://chromiumcodereview.appspot.com/10823300/diff/3/webkit/media/webmediap...
File webkit/media/webmediaplayer_impl.cc (right):

https://chromiumcodereview.appspot.com/10823300/diff/3/webkit/media/webmediap...
webkit/media/webmediaplayer_impl.cc:691: offset *
base::Time::kMicrosecondsPerSecond);
On 2012/08/14 02:00:44, Ami Fischman wrote:
> I suspect this wants to use webmediaplayer_util.h, but that can be another CL.

OK, Not Done Yet.