Reviewed by Dimitri Glazkov.

        Add window.performance.navigation namespace
        https://bugs.webkit.org/show_bug.cgi?id=41442

        Adds window.performance.navigation namespace consisting of ".type"
        and ".redirectCount". As part of this change, I renmaed "NavigationTiming"
        to just "Timing" to avoid confusion.

        No new tests because tests will be added in a subsequent patch when
        functionality is added.

        * Android.mk:
        * CMakeLists.txt:
        * DerivedSources.cpp:
        * DerivedSources.make:
        * GNUmakefile.am:
        * WebCore.gypi:
        * WebCore.pri:
        * WebCore.pro:
        * WebCore.vcproj/WebCore.vcproj:
        * WebCore.xcodeproj/project.pbxproj:
        * page/Navigation.cpp: Added.
        (WebCore::Navigation::Navigation):
        (WebCore::Navigation::frame):
        (WebCore::Navigation::disconnectFrame):
        (WebCore::Navigation::type):
        (WebCore:...