[chromium] Notify compositor of wheel event registration via ScrollingCoordinator

[chromium] Notify compositor of wheel event registration via ScrollingCoordinator
https://bugs.webkit.org/show_bug.cgi?id=79133

Reviewed by Dimitri Glazkov.

Source/WebCore:

This notifies the chromium compositor of changes to the number of wheel event handlers via ScrollingCoordinator
instead of through ChromeClient/WebViewImpl. This is the path we'll use for other properties in the future and
is more extensible for handling things other than the root layer.

Property behavior is covered by new unit tests in LayerChromiumTests and CCLayerTreeHostImplTest.

* page/scrolling/ScrollingCoordinator.cpp:
* page/scrolling/ScrollingCoordinator.h:
(WebCore):
(ScrollingCoordinator):
    Add a ScrollingCoordinatorPrivate so implementations can tack on additional data without having to #ifdef up
    ScrollingCoordinator.h/cpp
* page/scrolling/ScrollingCoordinatorNone.cpp:
(WebCore):
(WebCore::ScrollingCoordinator::~ScrollingCoordinator):
* page/scrolling/chromium/ScrollingCoordinatorChromium.cpp:
(ScrollingCoordinatorPrivate):
    ScrollingCoordinatorPrivate in the chromium implementation keeps a reference to the scroll layer.
(WebCore::ScrollingCoordinatorPrivate::ScrollingCoordinatorPrivate):
(WebCore::ScrollingCoordinatorPrivate::~ScrollingCoordinatorPrivate):
(WebCore::ScrollingCoordinatorPrivate::setScrollLayer):
(WebCore::ScrollingCoordinatorPrivate::scrollLayer):
(WebCore):
(WebCore::ScrollingCoordinator::create):
(WebCore::ScrollingCoordinator::~ScrollingCoordinator):
(WebCore::ScrollingCoordinator::frameViewHorizontalScrollbarLayerDidChange):
(WebCore::ScrollingCoordinator::frameViewVerticalScrollbarLayerDidChange):
(WebCore::ScrollingCoordinator::setScrollLayer):
(WebCore::ScrollingCoordinator::setNonFastScrollableRegion):
(WebCore::ScrollingCoordinator::setScrollParameters):
(WebCore::ScrollingCoordinator::setWheelEventHandlerCount):
(WebCore::ScrollingCoordinator::setShouldUpdateScrollLayerPositionOnMainThread):
* page/scrolling/mac/ScrollingCoordinatorMac.mm:
(WebCore):
(WebCore::ScrollingCoordinator::~ScrollingCoordinator):
* platform/graphics/chromium/LayerChromium.cpp:
(WebCore::LayerChromium::LayerChromium):
(WebCore::LayerChromium::setHaveWheelEventHandlers):
(WebCore):
(WebCore::LayerChromium::pushPropertiesTo):
* platform/graphics/chromium/LayerChromium.h:
(LayerChromium):
* platform/graphics/chromium/cc/CCInputHandler.h:
* platform/graphics/chromium/cc/CCLayerImpl.cpp:
(WebCore::CCLayerImpl::CCLayerImpl):
* platform/graphics/chromium/cc/CCLayerImpl.h:
(WebCore::CCLayerImpl::haveWheelEventHandlers):
(WebCore::CCLayerImpl::setHaveWheelEventHandlers):
(CCLayerImpl):
* platform/graphics/chromium/cc/CCLayerTreeHost.cpp:
(WebCore::CCLayerTreeHost::CCLayerTreeHost):
(WebCore::CCLayerTreeHost::finishCommitOnImplThread):
* platform/graphics/chromium/cc/CCLayerTreeHost.h:
(CCLayerTreeHost):
* platform/graphics/chromium/cc/CCLayerTreeHostImpl.cpp:
(WebCore::CCLayerTreeHostImpl::CCLayerTreeHostImpl):
(WebCore::CCLayerTreeHostImpl::scrollBegin):
* platform/graphics/chromium/cc/CCLayerTreeHostImpl.h:
(CCLayerTreeHostImpl):

Source/WebKit/chromium:

Rips out old wheel event notification and adds unit tests for new LayerChromium property.

* src/NonCompositedContentHost.cpp:
(WebKit::NonCompositedContentHost::setViewport):
* src/WebCompositorInputHandlerImpl.cpp:
(WebKit::WebCompositorInputHandlerImpl::handleInputEvent):
* src/WebViewImpl.cpp:
(WebKit::WebViewImpl::numberOfWheelEventHandlersChanged):
(WebKit::WebViewImpl::setIsAcceleratedCompositingActive):
* src/WebViewImpl.h:
* tests/CCLayerTreeHostImplTest.cpp:
(WebKit::TEST_F):
(WebKit):
* tests/LayerChromiumTest.cpp:
* tests/WebCompositorInputHandlerImplTest.cpp:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@108698 268f45cc-cd09-0410-ab3c-d52691b4dbfc