Query the system for the blink interval setting.

src/webkit/port/rendering/RenderThemeWin.cpp

 /*
  * This file is part of the WebKit project.
  *
  * Copyright (C) 2006 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 164 matching lines @@
 }
 
 static void setSizeIfAuto(RenderStyle* style, const IntSize& size)
 {
     if (style->width().isIntrinsicOrAuto())
         style->setWidth(Length(size.width(), Fixed));
     if (style->height().isAuto())
         style->setHeight(Length(size.height(), Fixed));
 }
 
+static double querySystemBlinkInterval(double defaultInterval) {
+    UINT blinkTime = ::GetCaretBlinkTime();
+    if (blinkTime == 0)
+        return defaultInterval;
+    if (blinkTime == INFINITE)
+        return 0;
+    return blinkTime / 1000.0;
+}
+
 // Implement WebCore::theme() for getting the global RenderTheme.
 RenderTheme* theme()
 {
     static RenderThemeWin winTheme;
     return &winTheme;
 }
 
 bool RenderThemeWin::supportsFocusRing(const RenderStyle* style) const
 {
    // Let webkit draw one of its halo rings around any focused element,
@@ skipping 41 matching lines @@
     return Color(255, 255, 150);
 }
 
 double RenderThemeWin::caretBlinkFrequency() const
 {
     // Disable the blinking caret in layout test mode, as it introduces
     // a race condition for the pixel tests. http://b/1198440
     if (ChromiumBridge::layoutTestMode())
         return 0;
 
-    // TODO(ericroman): this should be using the platform's blink frequency.
-    return RenderTheme::caretBlinkFrequency();
+    // This involves a system call, so we cache the result.
+    static double blinkInterval = querySystemBlinkInterval(RenderTheme::caretBlinkFrequency());
+    return blinkInterval;
 }
 
 void RenderThemeWin::systemFont(int propId, Document* document, FontDescription& fontDescription) const
 {
     // This logic owes much to RenderThemeSafari.cpp.
     FontDescription* cachedDesc = NULL;
     wchar_t* faceName = 0;
     float fontSize = 0;
     switch (propId) {
         case CSSValueSmallCaption:
@@ skipping 350 matching lines @@
 // static
 void RenderThemeWin::setFindInPageMode(bool enable) {
   if (m_findInPageMode == enable)
       return;
 
   m_findInPageMode = enable;
   theme()->platformColorsDidChange();
 }
 
 }  // namespace WebCore