Revert 196930 "Window.postMessage() to self can cause document l..."

Revert 196930 "Window.postMessage() to self can cause document l..."

Caused crashes in blink::PostMessageTimer::fired.
See https://code.google.com/p/chromium/issues/detail?id=499692 for more details.


> Window.postMessage() to self can cause document leaks
> 
> When a script does Window.postMessage() a PostMessageTimer object is
> stored in the LocalDOMWindow until the message has been delivered, or
> until it is cleared in the destructor of LocalDOMWindow. When a
> LocalDOMWindow is reset the remaining messages will not be
> delivered. Any PostMessageTimer objects alive at that point will be
> kept until the LocalDOMWindow is destroyed. Unfortunately, the
> PostMessageTimer objects keeps a reference to the source window. If
> both the source and destination window of the message is the same, the
> PostMessageTimer can keep that LocalDOMWindow from getting destroyed.
> 
> Removing the PostMessageTimers when stop() is invoked fixes the problem.
> 
> BUG=
> 
> Review URL: https://codereview.chromium.org/1148133005

TBR=landell@opera.com

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197009

[haraken, 2015-06-12 07:24:41]

Committed patchset #1 (id:1) manually as r197009.