Move Mime type handling to streamsPrivate API, so that it works on Desktop Chrome.

chrome/common/extensions/permissions/permission_set_unittest.cc

Index: chrome/common/extensions/permissions/permission_set_unittest.cc
diff --git a/chrome/common/extensions/permissions/permission_set_unittest.cc b/chrome/common/extensions/permissions/permission_set_unittest.cc
index 72d39a9858ccc5d171c8b7fc1e07c253a861f411..105ee8e538f07c2da875617210842763304fe2b6 100644
--- a/chrome/common/extensions/permissions/permission_set_unittest.cc
+++ b/chrome/common/extensions/permissions/permission_set_unittest.cc
@@ -720,6 +720,7 @@ TEST(PermissionsTest, PermissionMessages) {
   skip.insert(APIPermission::kMetricsPrivate);
   skip.insert(APIPermission::kNetworkingPrivate);
   skip.insert(APIPermission::kRtcPrivate);
+  skip.insert(APIPermission::kStreamsPrivate);
   skip.insert(APIPermission::kSystemPrivate);
   skip.insert(APIPermission::kTerminalPrivate);
   skip.insert(APIPermission::kWallpaperPrivate);