https://bugs.webkit.org/show_bug.cgi?id=75693

Reviewed by Eric Seidel.

We should have one class per file, on general principles.  Also, this
make it possible to use this class in DOMWindow without introducing a
circular include dependency.

* CMakeLists.txt:
* GNUmakefile.list.am:
* Target.pri:
* WebCore.gypi:
* WebCore.vcproj/WebCore.vcproj:
* page/Frame.cpp:
* page/Frame.h:
* page/FrameDestructionObserver.cpp: Added.
(WebCore::FrameDestructionObserver::FrameDestructionObserver):
(WebCore::FrameDestructionObserver::~FrameDestructionObserver):
(WebCore::FrameDestructionObserver::frameDestroyed):
* page/FrameDestructionObserver.h: Added.
(WebCore::FrameDestructionObserver::frame):
* plugins/DOMMimeType.h:
* plugins/DOMPlugin.h:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@104344 268f45cc-cd09-0410-ab3c-d52691b4dbfc