Bug 872170 - Fix camera file saving with composite device storage. r=mikeh

dom/camera/DOMCameraControl.cpp

@@ -282,7 +282,8 @@ nsDOMCameraControl::StartRecording(const JS::Value& aOptions, nsIDOMDeviceStorag
   #endif
 
   nsCOMPtr<nsIFile> folder;
-  storageArea->GetRootDirectory(getter_AddRefs(folder));
+  rv = storageArea->GetRootDirectoryForFile(filename, getter_AddRefs(folder));
+  NS_ENSURE_SUCCESS(rv, rv);
   return mCameraControl->StartRecording(&options, folder, filename, onSuccess, onError);
 }
 

dom/devicestorage/nsDeviceStorage.cpp

@@ -2932,12 +2932,20 @@ nsDOMDeviceStorage::Available(nsIDOMDOMRequest** aRetval)
 }
 
 NS_IMETHODIMP
-nsDOMDeviceStorage::GetRootDirectory(nsIFile** aRootDirectory)
+nsDOMDeviceStorage::GetRootDirectoryForFile(const nsAString& aName, nsIFile** aRootDirectory)
 {
-  if (!mRootDirectory) {
+  nsRefPtr<nsDOMDeviceStorage> ds;
+
+  if (IsComposite()) {
+    nsString storagePath;
+    ds = GetStorage(aName, storagePath);
+  } else {
+    ds = this;
+  }
+  if (!ds || !ds->mRootDirectory) {
     return NS_ERROR_FAILURE;
   }
-  return mRootDirectory->Clone(aRootDirectory);
+  return ds->mRootDirectory->Clone(aRootDirectory);
 }
 
 NS_IMETHODIMP

dom/interfaces/devicestorage/nsIDOMDeviceStorage.idl

@@ -16,7 +16,7 @@ dictionary DeviceStorageEnumerationParameters
   jsval since;
 };
 
-[scriptable, uuid(3d336180-b130-4b54-b205-ce74e36e733f), builtinclass]
+[scriptable, uuid(be690a9b-f0b4-4cde-a505-0b442abe2109), builtinclass]
 interface nsIDOMDeviceStorage : nsIDOMEventTarget
 {
     [implicit_jscontext] attribute jsval onchange;
@@ -48,5 +48,5 @@ interface nsIDOMDeviceStorage : nsIDOMEventTarget
     // include any path information.
     readonly attribute DOMString storageName;
 
-    [noscript] readonly attribute nsIFile rootDirectory;
+    [noscript] nsIFile getRootDirectoryForFile(in DOMString aName);
 };