Implement a Hit Test Cache.

Source/core/testing/Internals.cpp

Index: Source/core/testing/Internals.cpp
diff --git a/Source/core/testing/Internals.cpp b/Source/core/testing/Internals.cpp
index 90c01536ea43ac549d9a6eb9f6f4f27127e9db28..86e340656b3c6039b279f037b1fd3f7032c0fea3 100644
--- a/Source/core/testing/Internals.cpp
+++ b/Source/core/testing/Internals.cpp
@@ -317,6 +317,41 @@ unsigned Internals::hitTestCount(Document* doc, ExceptionState& exceptionState)
     return doc->layoutView()->hitTestCount();
 }
 
+unsigned Internals::hitTestCacheHits(Document* doc, ExceptionState& exceptionState) const
+{
+    if (!doc) {
+        exceptionState.throwDOMException(InvalidAccessError, "Must supply document to check");
+        return 0;
+    }
+
+    return doc->layoutView()->hitTestCacheHits();
+}
+
+Element* Internals::elementFromPointNoCache(Document* doc, double x, double y, ExceptionState& exceptionState) const
+{
+    if (!doc) {
+        exceptionState.throwDOMException(InvalidAccessError, "Must supply document to check");
+        return 0;
+    }
+
+    if (!doc->layoutView())
+        return 0;
+
+    return doc->elementFromPointNoCache(x, y);
+}
+
+void Internals::clearHitTestCache(Document* doc, ExceptionState& exceptionState) const
+{
+    if (!doc) {
+        exceptionState.throwDOMException(InvalidAccessError, "Must supply document to check");
+        return;
+    }
+
+    if (!doc->layoutView())
+        return;
+
+    doc->layoutView()->clearHitTestCache();
+}
 
 bool Internals::isPreloaded(const String& url)
 {