Rename runtime enabled check for prefixed Encrypted Media API.

Rename runtime enabled check for prefixed Encrypted Media API.

This will allow the prefixed and unprefixed versions to be controlled independently.
The new unprefixed runtime check is also added.

encryptedMediaAnyVersion enables MediaKeyError when either version is enabled
and is managed by the other controls.

BUG=224791
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=150618

[ddorwin, 2013-05-16 23:28:54]

This is similar to the runtime check changes in
https://codereview.chromium.org/14619016/. This CL also adds the new check,
which is required to enable ENCRYPTED_MEDIA_V2, at the same time.

[abarth-chromium, 2013-05-17 05:27:14]

lgtm

https://codereview.chromium.org/15016009/diff/1/Source/WebKit/chromium/public...
File Source/WebKit/chromium/public/WebRuntimeFeatures.h (right):

https://codereview.chromium.org/15016009/diff/1/Source/WebKit/chromium/public...
Source/WebKit/chromium/public/WebRuntimeFeatures.h:89: WEBKIT_EXPORT static bool
isWebKitEncryptedMediaEnabled();
enableDeprecatedEncryptedMedia ?  We're trying to get away from using the term
"webkit" in code.

[ddorwin, 2013-05-18 00:31:12]

Replaced "WebKit" with "Legacy". "WebKit" made sense in the MSE case because
there is an actual object named WebKitMediaSource. In the EME case, there are
various functions and events prefixed with "webkit" but no actual
WebKitEncryptedMedia. Since it's not yet deprecated, "Legacy" seemed better.

[abarth-chromium, 2013-05-18 00:44:10]

ok

[commit-bot: I haz the power, 2013-05-18 00:53:13]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/ddorwin@chromium.org/15016009/13001

[commit-bot: I haz the power, 2013-05-18 01:43:20]

Change committed as 150618