REGRESSION(r153112-r153296): 6-13% on Dromaeo/jslib-traverse-jquery and 4.5~7% on jslib-*-prototype

[Ryosuke Niwa]

https://perf.webkit.org/#mode=charts&chartList=%5B%5B%22mac-lion%22%2C%22Dromaeo%2Fjslib-attr-prototype%3ARuns%22%5D%2C%5B%22mac-mountainlion%22%2C%22Dromaeo%2Fjslib-attr-prototype%3ARuns%22%5D%5D&days=168&zoom=%5B1374149809806.9011%2C1375498325363.4504%5D

http://trac.webkit.org/log/?rev=153296&stop_rev=153112&verbose=on

Appears to be coming from the initial FTL merge.

[Ryosuke Niwa]

*** Bug 125949 has been marked as a duplicate of this bug. ***

[Ryosuke Niwa]

Dromaeo/jslib-event-prototype

https://perf.webkit.org/#mode=charts&chartList=%5B%5B%22mac-mountainlion%22%2C%22Dromaeo%2Fjslib-event-prototype%3ARuns%22%5D%2C%5B%22mac-lion%22%2C%22Dromaeo%2Fjslib-event-prototype%3ARuns%22%5D%5D&days=168&zoom=%5B1374309311646.923%2C1374932818839.7363%5D

Dromaeo/jslib-style-prototype

https://perf.webkit.org/#mode=charts&chartList=%5B%5B%22mac-mountainlion%22%2C%22Dromaeo%2Fjslib-style-prototype%3ARuns%22%5D%2C%5B%22mac-lion%22%2C%22Dromaeo%2Fjslib-style-prototype%3ARuns%22%5D%5D&days=227&zoom=%5B1374596496227.0615%2C1374765655445.4568%5D

[Ryosuke Niwa]

Also regressed Dromaeo/jslib-traverse-jquery by 6-13%:

https://perf.webkit.org/#mode=charts&chartList=%5B%5B%22mac-lion%22%2C%22Dromaeo%2Fjslib-traverse-jquery%3ARuns%22%5D%2C%5B%22mac-mountainlion%22%2C%22Dromaeo%2Fjslib-traverse-jquery%3ARuns%22%5D%5D&days=227&zoom=%5B1374296323262.5205%2C1375471806619.7832%5D

[Radar WebKit Bug Importer]

<rdar://problem/15711018>

[Radar WebKit Bug Importer]

<rdar://problem/15711019>