Page::chrome() should return a reference.

Source/core/page/Settings.cpp

Index: Source/core/page/Settings.cpp
diff --git a/Source/core/page/Settings.cpp b/Source/core/page/Settings.cpp
index c7ffbb153d202bfe4d1dcfbce8aa88d9f619e40c..5eb5677439591e6c4d7b20c357932aba8f4380e7 100644
--- a/Source/core/page/Settings.cpp
+++ b/Source/core/page/Settings.cpp
@@ -259,8 +259,8 @@ void Settings::setUseWideViewport(bool useWideViewport)
         return;
 
     m_useWideViewport = useWideViewport;
-    if (m_page->chrome() && m_page->mainFrame())
-        m_page->chrome()->dispatchViewportPropertiesDidChange(m_page->mainFrame()->document()->viewportArguments());
+    if (m_page->mainFrame())
+        m_page->chrome().dispatchViewportPropertiesDidChange(m_page->mainFrame()->document()->viewportArguments());
 }
 
 void Settings::setLoadWithOverviewMode(bool loadWithOverviewMode)
@@ -269,8 +269,8 @@ void Settings::setLoadWithOverviewMode(bool loadWithOverviewMode)
         return;
 
     m_loadWithOverviewMode = loadWithOverviewMode;
-    if (m_page->chrome() && m_page->mainFrame())
-        m_page->chrome()->dispatchViewportPropertiesDidChange(m_page->mainFrame()->document()->viewportArguments());
+    if (m_page->mainFrame())
+        m_page->chrome().dispatchViewportPropertiesDidChange(m_page->mainFrame()->document()->viewportArguments());
 }
 
 void Settings::setTextAutosizingFontScaleFactor(float fontScaleFactor)