[WeakMemoryCache 1a] Make Reference from Inspector to Resource weak, remove removedFromMemoryCache()

third_party/WebKit/Source/core/css/StyleSheetContents.h

Index: third_party/WebKit/Source/core/css/StyleSheetContents.h
diff --git a/third_party/WebKit/Source/core/css/StyleSheetContents.h b/third_party/WebKit/Source/core/css/StyleSheetContents.h
index 1a12b8a2d5a1104cbad97bb81fe573014cc7bd9b..079390e126dc054c95678c14c634a16319f12227 100644
--- a/third_party/WebKit/Source/core/css/StyleSheetContents.h
+++ b/third_party/WebKit/Source/core/css/StyleSheetContents.h
@@ -141,9 +141,9 @@ public:
 
     void removeSheetFromCache(Document*);
 
-    bool isInMemoryCache() const { return m_isInMemoryCache; }
-    void addedToMemoryCache();
-    void removedFromMemoryCache();
+    // A StyleSheetContents must not be shared by multiple Resource objects.

[rune, 2016/05/09 07:32:46]

I don't understand this comment. Isn't this flag about the fact that if
StyleSheetContents is cached, we must clone it, not mutate it, from CSSOM since
it may be used by another link using the cached resource later on?

[hiroshige, 2016/05/10 06:32:55]

I meant that when StyleSheetContents is cached, the StyleSheetContents is
referenced by only one Resource, not two or more.
I removed the comment because the comment can be confusing, and the assumption
is checked by ASSERT() in setReferencedFromResource().

+    bool isReferencedFromResource() const { return m_isReferencedFromResource; }
+    void setReferencedFromResource(bool);
 
     void setHasMediaQueries();
     bool hasMediaQueries() const { return m_hasMediaQueries; }
@@ -181,7 +181,7 @@ private:
     bool m_hasSyntacticallyValidCSSHeader : 1;
     bool m_didLoadErrorOccur : 1;
     bool m_isMutable : 1;
-    bool m_isInMemoryCache : 1;
+    bool m_isReferencedFromResource : 1;
     bool m_hasFontFaceRule : 1;
     bool m_hasMediaQueries : 1;
     bool m_hasSingleOwnerDocument : 1;