Revert of Oilpan: Use weak pointers in StyleSheetContents caches.

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 2de67f7ad04984c5061f54ba1091979247803928..f59a38e203d880478af6b41ac56e4eeaad749b46 100644
--- a/Source/core/dom/StyleEngine.cpp
+++ b/Source/core/dom/StyleEngine.cpp
@@ -54,28 +54,18 @@
 
 using namespace HTMLNames;
 
-static WillBeHeapHashMap<AtomicString, RawPtrWillBeWeakMember<StyleSheetContents> >& textToSheetCache()
-{
-    typedef WillBeHeapHashMap<AtomicString, RawPtrWillBeWeakMember<StyleSheetContents> > TextToSheetCache;
-#if ENABLE(OILPAN)
-    DEFINE_STATIC_LOCAL(Persistent<TextToSheetCache>, cache, (new TextToSheetCache));
-    return *cache;
-#else
+static HashMap<AtomicString, StyleSheetContents*>& textToSheetCache()
+{
+    typedef HashMap<AtomicString, StyleSheetContents*> TextToSheetCache;
     DEFINE_STATIC_LOCAL(TextToSheetCache, cache, ());
     return cache;
-#endif
-}
-
-static WillBeHeapHashMap<RawPtrWillBeWeakMember<StyleSheetContents>, AtomicString>& sheetToTextCache()
-{
-    typedef WillBeHeapHashMap<RawPtrWillBeWeakMember<StyleSheetContents>, AtomicString> SheetToTextCache;
-#if ENABLE(OILPAN)
-    DEFINE_STATIC_LOCAL(Persistent<SheetToTextCache>, cache, (new SheetToTextCache));
-    return *cache;
-#else
+}
+
+static HashMap<StyleSheetContents*, AtomicString>& sheetToTextCache()
+{
+    typedef HashMap<StyleSheetContents*, AtomicString> SheetToTextCache;
     DEFINE_STATIC_LOCAL(SheetToTextCache, cache, ());
     return cache;
-#endif
 }
 
 StyleEngine::StyleEngine(Document& document)
@@ -589,7 +579,7 @@
     if (!e->document().inQuirksMode()) {
         AtomicString textContent(text);
 
-        WillBeHeapHashMap<AtomicString, RawPtrWillBeWeakMember<StyleSheetContents> >::AddResult result = textToSheetCache().add(textContent, RawPtrWillBeWeakMember<StyleSheetContents>(nullptr));
+        HashMap<AtomicString, StyleSheetContents*>::AddResult result = textToSheetCache().add(textContent, 0);
         if (result.isNewEntry || !result.storedValue->value) {
             styleSheet = StyleEngine::parseSheet(e, text, startPosition, createdByParser);
             if (result.isNewEntry && styleSheet->contents()->maybeCacheable()) {
@@ -620,7 +610,7 @@
 
 void StyleEngine::removeSheet(StyleSheetContents* contents)
 {
-    WillBeHeapHashMap<RawPtrWillBeWeakMember<StyleSheetContents>, AtomicString>::iterator it = sheetToTextCache().find(contents);
+    HashMap<StyleSheetContents*, AtomicString>::iterator it = sheetToTextCache().find(contents);
     if (it == sheetToTextCache().end())
         return;