Audited and renamed uses of methods and variables named RootView

Source/platform/HostWindow.h

Index: Source/platform/HostWindow.h
diff --git a/Source/platform/HostWindow.h b/Source/platform/HostWindow.h
index f0874c31a58d39501d494957a4c9b7b3845db2ba..9065dd63bb3810276d0d0f42cb2e7e407176befe 100644
--- a/Source/platform/HostWindow.h
+++ b/Source/platform/HostWindow.h
@@ -50,8 +50,8 @@ public:
     virtual void invalidateDisplayItemClient(DisplayItemClient) { }
     virtual void invalidateAllDisplayItems() { }
 
-    // Methods for doing coordinate conversions to screen coordinates.
-    virtual IntRect rootViewToScreen(const IntRect&) const = 0;
+    // Converts from the window coordinates to screen coordinates.
+    virtual IntRect viewportToScreen(const IntRect&) const = 0;
 
     virtual WebScreenInfo screenInfo() const = 0;