Measure usage of HTMLMediaElement preload states

Measure usage of HTMLMediaElement preload states

Refactoring into a preloadType() is necessary in order to count cases
where the preload attribute is never set, i.e. the missing value default
case. Also, it's nice to have less state in HTMLMediaElement.

BUG=73609, 310450
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=198955

[philipj_slow, 2015-07-15 09:36:54]

The CQ bit was checked by philipj@opera.com to run a CQ dry run

[commit-bot: I haz the power, 2015-07-15 09:37:04]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1227403004/1

[philipj_slow, 2015-07-15 10:46:02]

philipj@opera.com changed reviewers:
+ fs@opera.com

[philipj_slow, 2015-07-15 10:46:02]

PTAL

[philipj_slow, 2015-07-15 10:48:14]

I had written this in the description: "There are bugs around preload on the
very lines touched, which will be addressed in a follow-up CL. This CL should
not change any behavior."

I removed that, because the bugs aren't precisely what I thought. It looks to me
like setting preload="none" and the autoplay ought to fail to load, but
https://github.com/w3c/web-platform-tests/blob/master/html/semantics/embedded...
actually passes without the fix, so I'll have to investigate further. This CL
should still be OK though.

[commit-bot: I haz the power, 2015-07-15 10:49:09]

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

[commit-bot: I haz the power, 2015-07-15 10:49:09]

Dry run: This issue passed the CQ dry run.

[fs, 2015-07-15 11:07:51]

lgtm

https://codereview.chromium.org/1227403004/diff/1/Source/core/html/HTMLMediaE...
File Source/core/html/HTMLMediaElement.cpp (right):

https://codereview.chromium.org/1227403004/diff/1/Source/core/html/HTMLMediaE...
Source/core/html/HTMLMediaElement.cpp:1893: const AtomicString& preload =
getAttribute(preloadAttr);
Nit: fastGetAttribute?

[philipj_slow, 2015-07-15 12:30:25]

https://codereview.chromium.org/1227403004/diff/1/Source/core/html/HTMLMediaE...
File Source/core/html/HTMLMediaElement.cpp (right):

https://codereview.chromium.org/1227403004/diff/1/Source/core/html/HTMLMediaE...
Source/core/html/HTMLMediaElement.cpp:1893: const AtomicString& preload =
getAttribute(preloadAttr);
On 2015/07/15 11:07:50, fs wrote:
> Nit: fastGetAttribute?

Yes of course, thanks :)

[philipj_slow, 2015-07-15 12:34:48]

The CQ bit was checked by philipj@opera.com

[philipj_slow, 2015-07-15 12:34:49]

The patchset sent to the CQ was uploaded after l-g-t-m from fs@opera.com
Link to the patchset: https://codereview.chromium.org/1227403004/#ps20001
(title: "Use fastGetAttribute")

[commit-bot: I haz the power, 2015-07-15 12:35:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1227403004/20001

[commit-bot: I haz the power, 2015-07-15 13:47:14]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=198955