https://bugs.webkit.org/show_bug.cgi?id=125471

Reviewed by Sam Weinig.

* Shared/APIFrameHandle.cpp: Added.
* Shared/APIFrameHandle.h: Added.
Add a new API::FrameHandle class that represents a frame.

* Shared/APIObject.h:
* Shared/APIPageHandle.cpp: Added.
* Shared/APIPageHandle.h: Added.
Add a new API::PageHandle class that represents a page.

* Shared/UserData.cpp: Added.
(WebKit::UserData::UserData):
(WebKit::UserData::~UserData):
(WebKit::UserData::encode):
(WebKit::UserData::decode):
* Shared/UserData.h: Added.
Add a UserData class that can be encoded and decoded. This will be used for sending data
 between the web process and UI process without doing any of the Page -> BundlePage etc conversions.
* WebKit2.xcodeproj/project.pbxproj:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@160341 268f45cc-cd09-0410-ab3c-d52691b4dbfc