Move deprecation messages to UseCounter::measureDeprecatedFeature.

Move deprecation messages to UseCounter::measureDeprecatedFeature.

Currently, deprecation messages are generated and deduplicated inside
PageConsole::reportDeprecation. The functionality directly replicates
UseCounter's BitVector-based deduplication, and it forces us to store
another list of features in PageConsole::DeprecatedFeatures. This can
be greatly simplified by moving the functionality into UseCounter,
making it a one-stop-shop for measurement and deprecation (we might
want to rename it at some point).

This has a few advantages. Most importantly, we can ensure that every
deprecated feature is measured. This patch adds histogram measurement
to `AudioBufferSourceNode.looping`, `HTMLMediaElement.webkitAddKey`,
and `HTMLMediaElement.webkitGenerateKeyRequest`, for instance. Going
forward, it will be impossible to miss these, as the mechanism is the
same.

At the same time, this patch allows us to move some of the deprecation
work to IDL files: we don't need to notify explicitly if we can declare
deprecation via the 'DeprecateAs' IDL attribute. This allows us to
remove the explicit deprecation from HTMLMediaElement::webkitAddKey,
HTMLMediaElement::webkitGenerateKeyRequest, and
DOMWindowQuota::webkitStorageInfo. More to come.

BUG=233522
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=149184

[Use mkwst_at_chromium.org plz., 2013-04-25 11:48:13]

Hi Kentaro-san and Jochen! Would you mind taking a look at the bindings/IDL
portions of this patch?

Adam and Eric, I hope you can take a few minutes to evaluate the API changes. In
a nutshell, this moves deprecation from PageConsole::reportDeprecation to
UseCounter::measureDeprecatedFeature (if this lands, I'd like to rename
UseCounter::observe to UseCounter::measureFeature in a future patch for
consistency).

The goal is simply to ensure that each deprecated feature is measured via
UseCounter, as we'll otherwise never know when to kill them. This patch means
that we store one list of "interesting" features in UseCounter::Feature, and
simply pick certain ones off that list to deprecate by adding messages in to
getDeprecationMessage.

WDYT?

-mike

[abarth-chromium, 2013-04-26 03:56:06]

Brilliant.  LGTM.

https://codereview.chromium.org/14146021/diff/5001/Source/core/page/UseCounte...
File Source/core/page/UseCounter.cpp (right):

https://codereview.chromium.org/14146021/diff/5001/Source/core/page/UseCounte...
Source/core/page/UseCounter.cpp:35: #include <wtf/text/WTFString.h>
Please use normal " " marks for wtf.  It's not special in any way.

https://codereview.chromium.org/14146021/diff/5001/Source/core/page/UseCounter.h
File Source/core/page/UseCounter.h (right):

https://codereview.chromium.org/14146021/diff/5001/Source/core/page/UseCounte...
Source/core/page/UseCounter.h:145: String getDeprecationMessage(Feature);
getDeprecationMessage -> deprecationMessage (the prefix "get" adds no
information)

[ojan, 2013-04-26 04:34:46]

Looks great! One comment nit.

https://codereview.chromium.org/14146021/diff/5001/Source/core/page/UseCounter.h
File Source/core/page/UseCounter.h (right):

https://codereview.chromium.org/14146021/diff/5001/Source/core/page/UseCounte...
Source/core/page/UseCounter.h:140: // "measureDeprecation" sets the bit for this
feature to 1, and sends a deprecation warning to the console.
I'd prefer if this had an extra comment that people should only use this API if
the feature is expected to be removed in the next release or two. We've had
issues in the past where people logged warnings to the console of things that
couldn't realistically be removed anytime soone and just created a lot of
console spam.

[commit-bot: I haz the power, 2013-04-26 08:42:09]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mkwst@chromium.org/14146021/11001

[commit-bot: I haz the power, 2013-04-26 08:42:18]

Failed to apply patch for Source/modules/quota/DOMWindowQuota.idl:
While running patch -p1 --forward --force --no-backup-if-mismatch;
  patching file Source/modules/quota/DOMWindowQuota.idl
  Hunk #1 FAILED at 26.
  1 out of 1 hunk FAILED -- saving rejects to file
Source/modules/quota/DOMWindowQuota.idl.rej

Patch:       Source/modules/quota/DOMWindowQuota.idl
Index: Source/modules/quota/DOMWindowQuota.idl
diff --git a/Source/modules/quota/DOMWindowQuota.idl
b/Source/modules/quota/DOMWindowQuota.idl
index
225efeffce61e8cd4f019d2caf1c69343a9f61a8..688b1f2563b878af880e23e45895533337b651f0
100644
--- a/Source/modules/quota/DOMWindowQuota.idl
+++ b/Source/modules/quota/DOMWindowQuota.idl
@@ -26,6 +26,6 @@
 [
     Supplemental=DOMWindow
 ] interface DOMWindowQuota {
-    [MeasureAs=StorageInfo] readonly attribute StorageInfo webkitStorageInfo;
+    [DeprecateAs=StorageInfo] readonly attribute StorageInfo webkitStorageInfo;
 };

[commit-bot: I haz the power, 2013-04-26 08:45:36]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mkwst@chromium.org/14146021/15002

[commit-bot: I haz the power, 2013-04-26 08:51:42]

Presubmit check for 14146021-15002 failed and returned exit status -2001.
The presubmit check was hung. It took 360.0 seconds to execute and the time
limit is 360.0 seconds.

INFO:root:Found 16 file(s).

[Mike West, 2013-04-26 08:54:41]

Committed patchset #4 manually as r149184 (presubmit successful).