Move inline stylesheet cache decision making from StyleSheetContents to StyleEngine

Source/core/css/StyleSheetContents.h

Index: Source/core/css/StyleSheetContents.h
diff --git a/Source/core/css/StyleSheetContents.h b/Source/core/css/StyleSheetContents.h
index 90acc818cd9c85ab313221d08a4defd2cfbeb9a1..ad289d2688d5cbc6a0ab3e2949a67d2f6ada29b1 100644
--- a/Source/core/css/StyleSheetContents.h
+++ b/Source/core/css/StyleSheetContents.h
@@ -71,7 +71,6 @@ public:
     bool parseStringAtPosition(const String&, const TextPosition&, bool);
 
     bool isCacheable() const;
-    bool maybeCacheable() const;
 
     bool isLoading() const;
 
@@ -154,7 +153,9 @@ public:
     void removedFromMemoryCache();
 
     void setHasMediaQueries();
-    bool hasMediaQueries() { return m_hasMediaQueries; }
+    bool hasMediaQueries() const { return m_hasMediaQueries; }
+
+    bool didLoadErrorOccur() const { return m_didLoadErrorOccur; }
 
     void shrinkToFit();
     RuleSet& ruleSet() { ASSERT(m_ruleSet); return *m_ruleSet.get(); }