Bug 1317720. Use NeedsCallerType instead of NeedsSubjectPrincipal for DataTransfer.types. r=mystor

dom/events/DataTransfer.cpp

@@ -311,8 +311,7 @@ DataTransfer::GetFiles(nsIDOMFileList** aFileList)
 }
 
 void
-DataTransfer::GetTypes(nsTArray<nsString>& aTypes,
-                       nsIPrincipal& aSubjectPrincipal) const
+DataTransfer::GetTypes(nsTArray<nsString>& aTypes, CallerType aCallerType) const
 {
   // When called from bindings, aTypes will be empty, but since we might have
   // Gecko-internal callers too, clear it to be safe.
@@ -327,7 +326,7 @@ DataTransfer::GetTypes(nsTArray<nsString>& aTypes,
     DataTransferItem* item = items->ElementAt(i);
     MOZ_ASSERT(item);
 
-    if (item->ChromeOnly() && !nsContentUtils::IsSystemPrincipal(&aSubjectPrincipal)) {
+    if (item->ChromeOnly() && aCallerType != CallerType::System) {
       continue;
     }
 

dom/events/DataTransfer.h

@@ -136,8 +136,7 @@ public:
   void SetDragImage(Element& aElement, int32_t aX, int32_t aY,
                     ErrorResult& aRv);
 
-  void GetTypes(nsTArray<nsString>& aTypes,
-                nsIPrincipal& aSubjectPrincipal) const;
+  void GetTypes(nsTArray<nsString>& aTypes, CallerType aCallerType) const;
 
   void GetData(const nsAString& aFormat, nsAString& aData,
                nsIPrincipal& aSubjectPrincipal,

dom/webidl/DataTransfer.webidl

@@ -19,7 +19,7 @@ interface DataTransfer {
 
   // ReturnValueNeedsContainsHack on .types because lots of extension
   // code was expecting .contains() back when it was a DOMStringList.
-  [Pure, Cached, Frozen, NeedsSubjectPrincipal, ReturnValueNeedsContainsHack]
+  [Pure, Cached, Frozen, NeedsCallerType, ReturnValueNeedsContainsHack]
   readonly attribute sequence<DOMString> types;
   [Throws, NeedsSubjectPrincipal]
   DOMString getData(DOMString format);

editor/libeditor/EditorEventListener.cpp

@@ -935,7 +935,7 @@ EditorEventListener::CanDrop(nsIDOMDragEvent* aEvent)
   NS_ENSURE_TRUE(dataTransfer, false);
 
   nsTArray<nsString> types;
-  dataTransfer->GetTypes(types, *nsContentUtils::GetSystemPrincipal());
+  dataTransfer->GetTypes(types, CallerType::System);
 
   // Plaintext editors only support dropping text. Otherwise, HTML and files
   // can be dropped as well.

layout/forms/nsFileControlFrame.cpp

@@ -380,7 +380,7 @@ nsFileControlFrame::DnDListener::IsValidDropData(nsIDOMDataTransfer* aDOMDataTra
 
   // We only support dropping files onto a file upload control
   nsTArray<nsString> types;
-  dataTransfer->GetTypes(types, *nsContentUtils::GetSystemPrincipal());
+  dataTransfer->GetTypes(types, CallerType::System);
 
   return types.Contains(NS_LITERAL_STRING("Files"));
 }