Use C++11 range-based loop for core/clipboard, core/dom and core/testing

Source/core/dom/StyleEngine.cpp

Index: Source/core/dom/StyleEngine.cpp
diff --git a/Source/core/dom/StyleEngine.cpp b/Source/core/dom/StyleEngine.cpp
index 3cf7628102fe7cb30228dd8be63d995839a14378..af68e4470dbd128ae6e271ae7b92b0996e382688 100644
--- a/Source/core/dom/StyleEngine.cpp
+++ b/Source/core/dom/StyleEngine.cpp
@@ -347,8 +347,8 @@ bool StyleEngine::shouldUpdateShadowTreeStyleSheetCollection(StyleResolverUpdate
 
 void StyleEngine::clearMediaQueryRuleSetOnTreeScopeStyleSheets(TreeScopeSet treeScopes)
 {
-    for (TreeScopeSet::iterator it = treeScopes.begin(); it != treeScopes.end(); ++it) {
-        TreeScope& treeScope = **it;
+    for (TreeScope* scope : treeScopes) {
+        TreeScope& treeScope = *scope;
         ASSERT(treeScope != m_document);
         ShadowTreeStyleSheetCollection* collection = static_cast<ShadowTreeStyleSheetCollection*>(styleSheetCollectionFor(treeScope));
         ASSERT(collection);
@@ -387,8 +387,7 @@ void StyleEngine::updateActiveStyleSheets(StyleResolverUpdateMode updateMode)
         TreeScopeSet treeScopes = updateMode == FullStyleUpdate ? m_activeTreeScopes : m_dirtyTreeScopes;
         HashSet<TreeScope*> treeScopesRemoved;
 
-        for (TreeScopeSet::iterator it = treeScopes.begin(); it != treeScopes.end(); ++it) {
-            TreeScope* treeScope = *it;
+        for (TreeScope* treeScope : treeScopes) {
             ASSERT(treeScope != m_document);
             ShadowTreeStyleSheetCollection* collection = static_cast<ShadowTreeStyleSheetCollection*>(styleSheetCollectionFor(*treeScope));
             ASSERT(collection);