Use WebURL parameter type for storagePartition in queryStorageUsageAndQuota
Use WebURL parameter type for storagePartition in queryStorageUsageAndQuota

It'd be clearer since the callee side (chrome) uses the given parameter as GURL.

BUG=259660
TEST=no behavioral change

Review URL: https://chromiumcodereview.appspot.com/19774002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@154622 bbb929c8-8fbe-4397-9dbb-9b2b20218538

primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs