Rename usesOverlayScrollbars of settings to mockScrollbarsUseOverlay

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 1fbd650ac292dbe61a7119186cfadf6fb65fc03a..2245bb9c7c725a9811738a42308aa609566bd3bd 100644
--- a/Source/core/page/Settings.cpp
+++ b/Source/core/page/Settings.cpp
@@ -77,7 +77,7 @@ static inline const AtomicString& getGenericFontFamilyForScript(const ScriptFont
 }
 
 bool Settings::gMockScrollbarsEnabled = false;
-bool Settings::gUsesOverlayScrollbars = false;
+bool Settings::gMockScrollbarsUseOverlay = false;
 
 // NOTEs
 //  1) EditingMacBehavior comprises builds on Mac;
@@ -359,14 +359,14 @@ bool Settings::mockScrollbarsEnabled()
     return gMockScrollbarsEnabled;
 }
 
-void Settings::setUsesOverlayScrollbars(bool flag)
+void Settings::setMockScrollbarsUseOverlay(bool flag)
 {
-    gUsesOverlayScrollbars = flag;
+    gMockScrollbarsUseOverlay = flag;
 }
 
-bool Settings::usesOverlayScrollbars()
+bool Settings::mockScrollbarsUseOverlay()
 {
-    return gUsesOverlayScrollbars;
+    return gMockScrollbarsUseOverlay;
 }
 
 void Settings::setOpenGLMultisamplingEnabled(bool flag)