Centralize more querySelector logic behind QuerySelectorCache.

third_party/WebKit/Source/core/dom/ContainerNode.cpp

Index: third_party/WebKit/Source/core/dom/ContainerNode.cpp
diff --git a/third_party/WebKit/Source/core/dom/ContainerNode.cpp b/third_party/WebKit/Source/core/dom/ContainerNode.cpp
index 46aacf5a09266351f9e34286c481c4bf70ec6f1c..044ab80ed5035a41befd9e595f07cdbde0baf663 100644
--- a/third_party/WebKit/Source/core/dom/ContainerNode.cpp
+++ b/third_party/WebKit/Source/core/dom/ContainerNode.cpp
@@ -34,7 +34,6 @@
 #include "core/dom/NodeComputedStyle.h"
 #include "core/dom/NodeRareData.h"
 #include "core/dom/NodeTraversal.h"
-#include "core/dom/NthIndexCache.h"
 #include "core/dom/SelectorQuery.h"
 #include "core/dom/StaticNodeList.h"
 #include "core/dom/StyleChangeReason.h"
@@ -1173,36 +1172,20 @@ unsigned ContainerNode::countChildren() const {
 
 Element* ContainerNode::querySelector(const AtomicString& selectors,
                                       ExceptionState& exceptionState) {
-  if (selectors.isEmpty()) {
-    exceptionState.throwDOMException(SyntaxError,
-                                     "The provided selector is empty.");
-    return nullptr;
-  }
-
   SelectorQuery* selectorQuery = document().selectorQueryCache().add(
       selectors, document(), exceptionState);
   if (!selectorQuery)
     return nullptr;
-
-  NthIndexCache nthIndexCache(document());
   return selectorQuery->queryFirst(*this);
 }
 
 StaticElementList* ContainerNode::querySelectorAll(
     const AtomicString& selectors,
     ExceptionState& exceptionState) {
-  if (selectors.isEmpty()) {
-    exceptionState.throwDOMException(SyntaxError,
-                                     "The provided selector is empty.");
-    return nullptr;
-  }
-
   SelectorQuery* selectorQuery = document().selectorQueryCache().add(
       selectors, document(), exceptionState);
   if (!selectorQuery)
     return nullptr;
-
-  NthIndexCache nthIndexCache(document());
   return selectorQuery->queryAll(*this);
 }