Adds ability to prevent browser connection updates in layout tests.

Source/core/page/NetworkStateNotifier.cpp

Index: Source/core/page/NetworkStateNotifier.cpp
diff --git a/Source/core/page/NetworkStateNotifier.cpp b/Source/core/page/NetworkStateNotifier.cpp
index c4e4fe5248ff22a7e8627b716f02e003cc162780..e270afe6f12aff7f58acc853390e7fdc00e9b73b 100644
--- a/Source/core/page/NetworkStateNotifier.cpp
+++ b/Source/core/page/NetworkStateNotifier.cpp
@@ -60,6 +60,16 @@ void NetworkStateNotifier::setOnLine(bool onLine)
 void NetworkStateNotifier::setWebConnectionType(blink::WebConnectionType type)
 {
     ASSERT(isMainThread());
+    if (m_testUpdatesOnly)
+        return;
+
+    setWebConnectionTypeImpl(type);
+}
+
+void NetworkStateNotifier::setWebConnectionTypeImpl(blink::WebConnectionType type)
+{
+    ASSERT(isMainThread());
+    ASSERT(!m_testUpdatesOnly);
 
     MutexLocker locker(m_mutex);
     if (m_type == type)
@@ -106,6 +116,19 @@ void NetworkStateNotifier::removeObserver(NetworkStateObserver* observer, Execut
         collectZeroedObservers(observerList, context);
 }
 
+void NetworkStateNotifier::setTestUpdatesOnly(bool updatesOnly)
+{
+    ASSERT(isMainThread());
+    m_testUpdatesOnly = updatesOnly;
+}
+
+void NetworkStateNotifier::setWebConnectionTypeForTest(blink::WebConnectionType type)
+{
+    ASSERT(isMainThread());
+    ASSERT(m_testUpdatesOnly);
+    setWebConnectionTypeImpl(type);
+}
+
 void NetworkStateNotifier::notifyObserversOnContext(ExecutionContext* context, blink::WebConnectionType type)
 {
     ObserverList* observerList = lockAndFindObserverList(context);