Cleanup DocumentStyleSheetCollection

It seems a lot of code moved out of this class, so remove various includes and forward references.

Review URL: https://codereview.chromium.org/302093006

git-svn-id: svn://svn.chromium.org/blink/trunk@175211 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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

@@ -27,27 +27,16 @@
 #include "config.h"
 #include "core/dom/DocumentStyleSheetCollection.h"
 
-#include "HTMLNames.h"
 #include "RuntimeEnabledFeatures.h"
-#include "SVGNames.h"
-#include "core/css/CSSStyleSheet.h"
 #include "core/css/resolver/StyleResolver.h"
 #include "core/dom/Document.h"
 #include "core/dom/DocumentStyleSheetCollector.h"
-#include "core/dom/Element.h"
 #include "core/dom/ProcessingInstruction.h"
 #include "core/dom/StyleEngine.h"
 #include "core/dom/StyleSheetCandidate.h"
-#include "core/html/HTMLIFrameElement.h"
-#include "core/html/HTMLLinkElement.h"
-#include "core/html/HTMLStyleElement.h"
-#include "core/frame/Settings.h"
-#include "core/svg/SVGStyleElement.h"
 
 namespace WebCore {
 
-using namespace HTMLNames;
-
 DocumentStyleSheetCollection::DocumentStyleSheetCollection(TreeScope& treeScope)
     : TreeScopeStyleSheetCollection(treeScope)
 {

third_party/WebKit/Source/core/dom/DocumentStyleSheetCollection.h

@@ -32,9 +32,7 @@
 
 namespace WebCore {
 
-class CSSStyleSheet;
 class DocumentStyleSheetCollector;
-class StyleSheet;
 class StyleEngine;
 class TreeScope;