Surround fixedVisibleContentRect code with USE(TILED_BACKING_STORE)

https://bugs.webkit.org/show_bug.cgi?id=127461

Source/WebCore:

Reviewed by Andreas Kling.

The "fixedVisibleContentRect" code path is only used by platforms
which enabled TILED_BACKING_STORE, so to reduce confusion, surround
this code with #if USE(TILED_BACKING_STORE).

* page/Frame.cpp:
(WebCore::Frame::createView):
* page/FrameView.cpp:
* page/FrameView.h:
* platform/ScrollView.cpp:
(WebCore::ScrollView::unscaledVisibleContentSize):
(WebCore::ScrollView::visibleContentRect):
* platform/ScrollView.h:
(WebCore::ScrollView::visibleSize):

Source/WebKit2:

Reviewed by Andreas Kling.

The "fixedVisibleContentRect" code path is only used by platforms
which enabled TILED_BACKING_STORE, so to reduce confusion, surround
this code with #if USE(TILED_BACKING_STORE).

* WebProcess/WebCoreSupport/WebFrameLoaderClient.cpp:
(WebKit::WebFrameLoaderClient::transitionToCommittedForNewPage):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@162597 268f45cc-cd09-0410-ab3c-d52691b4dbfc