fetch: Align RequestInit's |headers| with the spec.

third_party/WebKit/Source/modules/fetch/Headers.h

Index: third_party/WebKit/Source/modules/fetch/Headers.h
diff --git a/third_party/WebKit/Source/modules/fetch/Headers.h b/third_party/WebKit/Source/modules/fetch/Headers.h
index 3c41b2d2df7ec92f29f081bb7408d9c289d1558a..c518128becf696d0445561720f106a6cad20ca60 100644
--- a/third_party/WebKit/Source/modules/fetch/Headers.h
+++ b/third_party/WebKit/Source/modules/fetch/Headers.h
@@ -55,8 +55,9 @@ class MODULES_EXPORT Headers final : public GarbageCollected<Headers>,
 
   // These methods should only be called when size() would return 0.
   void FillWith(const Headers*, ExceptionState&);
-  void FillWith(const Vector<Vector<String>>&, ExceptionState&);
-  void FillWith(const Vector<std::pair<String, String>>&, ExceptionState&);
+  void FillWith(
+      const ByteStringSequenceSequenceOrByteStringByteStringRecordOrHeaders&,

[yhirano, 2017/04/28 10:07:44]

Could you provide a typedef for this type? Maybe HeadersInit?

[Raphael Kubo da Costa (rakuco), 2017/05/01 09:57:12]

Done.

+      ExceptionState&);
 
   FetchHeaderList* HeaderList() const { return header_list_; }
   DECLARE_TRACE();
@@ -66,6 +67,10 @@ class MODULES_EXPORT Headers final : public GarbageCollected<Headers>,
   // Shares the FetchHeaderList. Called when creating a Request or Response.
   explicit Headers(FetchHeaderList*);
 
+  // These methods should only be called when size() would return 0.
+  void FillWith(const Vector<Vector<String>>&, ExceptionState&);
+  void FillWith(const Vector<std::pair<String, String>>&, ExceptionState&);
+
   Member<FetchHeaderList> header_list_;
   Guard guard_;