[chromium] Track separate scroll deltas on the compositor thread

[chromium] Track separate scroll deltas on the compositor thread
https://bugs.webkit.org/show_bug.cgi?id=69034

Reviewed by James Robinson.

Source/WebCore:

Test: new tests in CCLayerTreeHostImplTest/CCLayerTreeHostTest

Track scroll deltas and maximum scrolls on LayerChromium/CCLayerImpl.
The CCLayerImpl tree is now able to adjust these scroll deltas
independent of the main thread. To push them back to the main thread,
CCLayerTreeHostImpl collects them all and then bakes them into the
scroll position during a begin frame and commit call. This allows new
deltas to be collected while the scroll position containing the old
delta and the old scroll position will be overwritten during the next
commit.

Only the main frame is supported right now for pushing this scroll
delta back into the authoritative WebKit source to keep both sides in
sync.

Move tilingTransform() to the impl tree because drawTransform() is now
updated using scroll deltas and so the results from calculating draw
transforms needs to be dynamic so that children are updated properly.

Also, exposed DebugScopedSetImplThread public because it's used in a
few places.

* platform/graphics/chromium/LayerChromium.cpp:
(WebCore::LayerChromium::pushPropertiesTo):
* platform/graphics/chromium/LayerChromium.h:
(WebCore::LayerChromium::maxScrollPosition):
(WebCore::LayerChromium::setMaxScrollPosition):
(WebCore::LayerChromium::scrollDelta):
(WebCore::LayerChromium::scrollable):
* platform/graphics/chromium/NonCompositedContentHost.cpp:
(WebCore::NonCompositedContentHost::setViewport):
* platform/graphics/chromium/TiledLayerChromium.cpp:
(WebCore::TiledLayerChromium::pushPropertiesTo):
* platform/graphics/chromium/TiledLayerChromium.h:
* platform/graphics/chromium/cc/CCLayerImpl.cpp:
(WebCore::CCLayerImpl::scrollBy):
* platform/graphics/chromium/cc/CCLayerImpl.h:
(WebCore::CCLayerImpl::maxScrollPosition):
(WebCore::CCLayerImpl::setMaxScrollPosition):
(WebCore::CCLayerImpl::scrollDelta):
(WebCore::CCLayerImpl::setScrollDelta):
(WebCore::CCLayerImpl::scrollable):
* platform/graphics/chromium/cc/CCLayerTreeHost.cpp:
(WebCore::CCLayerTreeHost::applyScrollDeltas):
* platform/graphics/chromium/cc/CCLayerTreeHost.h:
* platform/graphics/chromium/cc/CCLayerTreeHostCommon.cpp:
(WebCore::calculateDrawTransformsAndVisibilityInternal):
* platform/graphics/chromium/cc/CCLayerTreeHostCommon.h:
* platform/graphics/chromium/cc/CCLayerTreeHostImpl.cpp:
(WebCore::CCLayerTreeHostImpl::scrollRootLayer):
(WebCore::CCLayerTreeHostImpl::processScrollDeltas):
* platform/graphics/chromium/cc/CCLayerTreeHostImpl.h:
* platform/graphics/chromium/cc/CCProxy.h:
* platform/graphics/chromium/cc/CCSingleThreadProxy.cpp:
(WebCore::CCSingleThreadProxy::start):
(WebCore::CCSingleThreadProxy::context):
(WebCore::CCSingleThreadProxy::finishAllRendering):
(WebCore::CCSingleThreadProxy::initializeLayerRenderer):
(WebCore::CCSingleThreadProxy::setNeedsCommit):
(WebCore::CCSingleThreadProxy::stop):
(WebCore::CCSingleThreadProxy::recreateContextIfNeeded):
(WebCore::CCSingleThreadProxy::commitIfNeeded):
(WebCore::CCSingleThreadProxy::doComposite):
* platform/graphics/chromium/cc/CCSingleThreadProxy.h:
(WebCore::DebugScopedSetImplThread::DebugScopedSetImplThread):
(WebCore::DebugScopedSetImplThread::~DebugScopedSetImplThread):
* platform/graphics/chromium/cc/CCThreadProxy.cpp:
(WebCore::CCThreadProxy::createBeginFrameAndCommitTaskOnCCThread):
(WebCore::CCThreadProxy::beginFrameAndCommit):
* platform/graphics/chromium/cc/CCThreadProxy.h:
* platform/graphics/chromium/cc/CCTiledLayerImpl.cpp:
(WebCore::CCTiledLayerImpl::tilingTransform):
(WebCore::CCTiledLayerImpl::draw):
* platform/graphics/chromium/cc/CCTiledLayerImpl.h:

Source/WebKit/chromium:

Add testing support for scroll deltas on layers.

* WebKit.gypi:
* src/WebViewImpl.cpp:
(WebKit::WebViewImpl::applyScrollDelta):
* src/WebViewImpl.h:
* tests/CCLayerTreeHostImplTest.cpp: Added.
(WebCore::CCLayerTreeHostImplTest::CCLayerTreeHostImplTest):
(WebCore::CCLayerTreeHostImplTest::expectClearedScrollDeltasRecursive):
(WebCore::CCLayerTreeHostImplTest::expectContains):
(WebCore::TEST_F):
* tests/CCLayerTreeHostTest.cpp:
(WTF::TestHooks::applyScrollDelta):
(WTF::MockLayerTreeHostClient::applyScrollDelta):
(WTF::CCLayerTreeHostTest::runTest):
(WTF::CCLayerTreeHostTest::doBeginTest):
(WTF::CCLayerTreeHostTestThreadOnly::runTest):
(WTF::CCLayerTreeHostTestScrollSimple::CCLayerTreeHostTestScrollSimple):
(WTF::CCLayerTreeHostTestScrollSimple::beginTest):
(WTF::CCLayerTreeHostTestScrollSimple::beginCommitOnCCThread):
(WTF::CCLayerTreeHostTestScrollSimple::drawLayersOnCCThread):
(WTF::CCLayerTreeHostTestScrollSimple::applyScrollDelta):
(WTF::CCLayerTreeHostTestScrollSimple::afterTest):
(WTF::TEST_F):
(WTF::CCLayerTreeHostTestScrollMultipleRedraw::CCLayerTreeHostTestScrollMultipleRedraw):
(WTF::CCLayerTreeHostTestScrollMultipleRedraw::beginTest):
(WTF::CCLayerTreeHostTestScrollMultipleRedraw::beginCommitOnCCThread):
(WTF::CCLayerTreeHostTestScrollMultipleRedraw::drawLayersOnCCThread):
(WTF::CCLayerTreeHostTestScrollMultipleRedraw::applyScrollDelta):
(WTF::CCLayerTreeHostTestScrollMultipleRedraw::afterTest):
* tests/TreeSynchronizerTest.cpp:
(WebCore::TEST):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@96454 268f45cc-cd09-0410-ab3c-d52691b4dbfc