Remove Apple's unused implementation of private browsing from WebCore

Source/WebCore/rendering/RenderSearchField.cpp

Index: Source/WebCore/rendering/RenderSearchField.cpp
diff --git a/Source/WebCore/rendering/RenderSearchField.cpp b/Source/WebCore/rendering/RenderSearchField.cpp
index ca0228c6d1b9c3a945c0e0eb1f05ac13580b0ecb..300c2ad5dd7ee1dabdb43cf59e1424dd25a9658e 100644
--- a/Source/WebCore/rendering/RenderSearchField.cpp
+++ b/Source/WebCore/rendering/RenderSearchField.cpp
@@ -91,10 +91,6 @@ void RenderSearchField::addSearchResult()
     if (value.isEmpty())
         return;
 
-    Settings* settings = document()->settings();
-    if (!settings || settings->privateBrowsingEnabled())
-        return;
-
     int size = static_cast<int>(m_recentSearches.size());
     for (int i = size - 1; i >= 0; --i) {
         if (m_recentSearches[i] == value)