[WIP] Add Resource::IsShareable

third_party/WebKit/Source/platform/loader/fetch/Resource.h

Index: third_party/WebKit/Source/platform/loader/fetch/Resource.h
diff --git a/third_party/WebKit/Source/platform/loader/fetch/Resource.h b/third_party/WebKit/Source/platform/loader/fetch/Resource.h
index 537d295485a5693ab14c937d77bd04f72eb61a1c..8ce429ce9634e33f3309569b7ad403c6af716505 100644
--- a/third_party/WebKit/Source/platform/loader/fetch/Resource.h
+++ b/third_party/WebKit/Source/platform/loader/fetch/Resource.h
@@ -307,6 +307,11 @@ class PLATFORM_EXPORT Resource : public GarbageCollectedFinalized<Resource>,
   }
 
   virtual bool CanReuse(const FetchParameters&) const { return true; }
+  virtual bool IsShareable() const {
+    // MemoryCache works only on the main thread, so we don't add a resource
+    // on another thread.
+    return IsMainThread() && options_.data_buffering_policy != kDoNotBufferData;
+  }
 
   // If cache-aware loading is activated, this callback is called when the first
   // disk-cache-only request failed due to cache miss. After this callback,