media: Pass DemuxerStreamProvider in Renderer::Initialize().

media: Pass DemuxerStreamProvider in Renderer::Initialize().

Currently DemuxerStreamProvider is passed in the constructor of Renderer
implementations (e.g. RendererImpl and MojoRendererImpl). However, if we want to
create the Renderer earlier and pass it to WebMediaPlayerImpl or Pipeline, the
DemuxerStreamProvider may not be available yet. Meanwhile, when Renderer is
initialized by the Pipeline, DemuxerStreamProvider is always available.

This CL moves the DemuxerStreamProvider parameter to Renderer::Initialize() to
accommodate the above cases.

BUG=416570
TEST=Unit tests updated.

Committed: https://crrev.com/abd95fd44fb0b36b06fa3a84f39472cff4d6386a
Cr-Commit-Position: refs/heads/master@{#298006}

[xhwang, 2014-09-22 23:50:40]

xhwang@chromium.org changed reviewers:
+ scherkus@chromium.org

[xhwang, 2014-09-22 23:50:40]

PTAL

[scherkus (not reviewing), 2014-09-23 00:55:12]

lgtm

OOC, which Renderer implementations do we create early?

[xhwang, 2014-10-03 05:41:14]

rebase only

[xhwang, 2014-10-03 05:42:37]

The CQ bit was checked by xhwang@chromium.org

[commit-bot: I haz the power, 2014-10-03 05:42:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/591203003/40001

[commit-bot: I haz the power, 2014-10-03 07:10:08]

Committed patchset #3 (id:40001) as dccea6433a38c1e8181307fdfb26ce049a4213b5

[commit-bot: I haz the power, 2014-10-03 07:10:41]

Patchset 3 (id:??) landed as
https://crrev.com/abd95fd44fb0b36b06fa3a84f39472cff4d6386a
Cr-Commit-Position: refs/heads/master@{#298006}