Restore in-memory parser cache for V8 compile.

Source/core/fetch/Resource.h

Index: Source/core/fetch/Resource.h
diff --git a/Source/core/fetch/Resource.h b/Source/core/fetch/Resource.h
index 157443890a34ee531010746355a4e7689b130fc3..42dffdcf6aca20f72c54c521c04bb96c42bcc96f 100644
--- a/Source/core/fetch/Resource.h
+++ b/Source/core/fetch/Resource.h
@@ -195,7 +195,10 @@ public:
     // Caches the given metadata in association with this resource and suggests
     // that the platform persist it. The dataTypeID is a pseudo-randomly chosen
     // identifier that is used to distinguish data generated by the caller.
-    void setCachedMetadata(unsigned dataTypeID, const char*, size_t);
+    // If persist is set, this will be sent to Platform::cacheMetadata for
+    // persistent caching by the embedder. Otherwise the caching is only
+    // in memory and therefore in-process.
+    void setCachedMetadata(unsigned dataTypeID, const char*, size_t, bool persist = true);
 
     // Reset existing metadata, to allow setting new data.
     void clearCachedMetadata();