Refactor WebMClusterParserTest parser creation for readability

Refactor WebMClusterParserTest parser creation for readability

This change adds some helpers to help readability of these tests,
addressing a review comment from
https://codereview.chromium.org/1235793005/.
It also moves some test statics into an unnamed namespace for style.

R=xhwang@chromium.org

Committed: https://crrev.com/c68af9b79bb64140686f59f5964da98d36ec0df0
Cr-Commit-Position: refs/heads/master@{#339750}

[wolenetz, 2015-07-21 00:50:19]

The CQ bit was checked by wolenetz@chromium.org to run a CQ dry run

[wolenetz, 2015-07-21 00:50:31]

Please take a look. Thanks!

[commit-bot: I haz the power, 2015-07-21 00:50:55]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1242943003/1

[commit-bot: I haz the power, 2015-07-21 01:30:29]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-07-21 01:30:29]

Dry run: This issue passed the CQ dry run.

[xhwang, 2015-07-21 04:28:31]

Looking good. Just one comment about function overloading.

https://codereview.chromium.org/1242943003/diff/1/media/formats/webm/webm_clu...
File media/formats/webm/webm_cluster_parser_unittest.cc (right):

https://codereview.chromium.org/1242943003/diff/1/media/formats/webm/webm_clu...
media/formats/webm/webm_cluster_parser_unittest.cc:103: WebMClusterParser*
CreateParser() {
Looking at the call sites below, it's a bit hard to track which version of
CreateParser() is called without looking at these definitions and comments.
Maybe we should follow the style guide more rigorously to favor more explicit
function names to function overloads. For example, this one can be
CreateDefaultParser.

[wolenetz, 2015-07-21 18:15:57]

Please take a look at patch set 2. Thanks!

https://codereview.chromium.org/1242943003/diff/1/media/formats/webm/webm_clu...
File media/formats/webm/webm_cluster_parser_unittest.cc (right):

https://codereview.chromium.org/1242943003/diff/1/media/formats/webm/webm_clu...
media/formats/webm/webm_cluster_parser_unittest.cc:103: WebMClusterParser*
CreateParser() {
On 2015/07/21 04:28:31, xhwang wrote:
> Looking at the call sites below, it's a bit hard to track which version of
> CreateParser() is called without looking at these definitions and comments.
> Maybe we should follow the style guide more rigorously to favor more explicit
> function names to function overloads. For example, this one can be
> CreateDefaultParser.

Done (and good point!) I hadn't read that particular overload style guidance
recently.

[xhwang, 2015-07-21 20:36:54]

lgtm

Thanks!

[wolenetz, 2015-07-21 20:51:31]

The CQ bit was checked by wolenetz@chromium.org

[commit-bot: I haz the power, 2015-07-21 20:52:16]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1242943003/20001

[commit-bot: I haz the power, 2015-07-21 21:21:07]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-07-21 21:22:08]

Patchset 2 (id:??) landed as
https://crrev.com/c68af9b79bb64140686f59f5964da98d36ec0df0
Cr-Commit-Position: refs/heads/master@{#339750}