Made Blink aware of top controls offset (Blink-side)

Source/web/WebViewImpl.cpp

Index: Source/web/WebViewImpl.cpp
diff --git a/Source/web/WebViewImpl.cpp b/Source/web/WebViewImpl.cpp
index 572e42bd4c3d09d6e3479a593b63e3b8d3a00b5e..477a43843620c60000da6ab3b1fbd2bc1c2c6702 100644
--- a/Source/web/WebViewImpl.cpp
+++ b/Source/web/WebViewImpl.cpp
@@ -412,6 +412,7 @@ WebViewImpl::WebViewImpl(WebViewClient* client)
     , m_backgroundColorOverride(Color::transparent)
     , m_zoomFactorOverride(0)
     , m_userGestureObserved(false)
+    , m_topControlsContentOffset(0)
 {
     Page::PageClients pageClients;
     pageClients.chromeClient = &m_chromeClientImpl;
@@ -1661,6 +1662,12 @@ void WebViewImpl::performResize()
     }
 }
 
+void WebViewImpl::setTopControlsContentOffset(float offset)
+{
+    m_topControlsContentOffset = offset;
+    m_layerTreeView->setTopControlsContentOffset(offset);
+}
+
 void WebViewImpl::resize(const WebSize& newSize)
 {
     if (m_shouldAutoResize || m_size == newSize)
@@ -4100,11 +4107,13 @@ void WebViewImpl::updateMainFrameScrollPosition(const IntPoint& scrollPosition,
     frameView->setInProgrammaticScroll(oldProgrammaticScroll);
 }
 
-void WebViewImpl::applyScrollAndScale(const WebSize& scrollDelta, float pageScaleDelta)
+void WebViewImpl::applyViewportDeltas(const WebSize& scrollDelta, float pageScaleDelta, float topControlsDelta)
 {
     if (!mainFrameImpl() || !mainFrameImpl()->frameView())
         return;
 
+    setTopControlsContentOffset(m_topControlsContentOffset + topControlsDelta);
+
     if (pinchVirtualViewportEnabled()) {
         if (pageScaleDelta != 1) {
             // When the virtual viewport is enabled, offsets are already set for us.