Expose WebPageImportanceSignals to embedder

Source/web/WebViewImpl.cpp

Index: Source/web/WebViewImpl.cpp
diff --git a/Source/web/WebViewImpl.cpp b/Source/web/WebViewImpl.cpp
index f57c51a0631416a97657ff5db47a1153b8dabf9e..8ab096360e417072101c83d8df7be769fe8f2972 100644
--- a/Source/web/WebViewImpl.cpp
+++ b/Source/web/WebViewImpl.cpp
@@ -482,6 +482,8 @@ WebViewImpl::WebViewImpl(WebViewClient* client)
     m_devToolsEmulator = DevToolsEmulator::create(this);
 
     allInstances().add(this);
+
+    m_pageImportanceSignals.setObserver(client);
 }
 
 WebViewImpl::~WebViewImpl()
@@ -3834,7 +3836,7 @@ void WebViewImpl::didCommitLoad(bool isNewNavigation, bool isNavigationWithinPag
 {
     if (isNewNavigation && !isNavigationWithinPage) {
         pageScaleConstraintsSet().setNeedsReset(true);
-        pageImportanceSignals().onCommitLoad();
+        m_pageImportanceSignals.onCommitLoad();
     }
 
     // Give the visual viewport's scroll layer its initial size.
@@ -4020,6 +4022,11 @@ void WebViewImpl::setPageOverlayColor(WebColor color)
     m_pageColorOverlay->update();
 }
 
+WebPageImportanceSignals* WebViewImpl::pageImportanceSignals()
+{
+    return &m_pageImportanceSignals;
+}
+
 Element* WebViewImpl::focusedElement() const
 {
     Frame* frame = m_page->focusController().focusedFrame();