Re-order member destruction in I18nSourceStreamTest

Avoid a spurious dangling ptr warning by dropping the unowned
reference to MockSourceStream before deleting the object which
owns it.

Bug: 1401495
Change-Id: I51cd2754e7933f8d55cdc0b0ddc9e38e4b2187d9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4241718
Reviewed-by: Avi Drissman <[email protected]>
Commit-Queue: Tom Sepez <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1104124}
diff --git a/ui/base/webui/i18n_source_stream_unittest.cc b/ui/base/webui/i18n_source_stream_unittest.cc
index b302077..094186d 100644
--- a/ui/base/webui/i18n_source_stream_unittest.cc
+++ b/ui/base/webui/i18n_source_stream_unittest.cc
@@ -158,8 +158,8 @@
   scoped_refptr<net::IOBuffer> output_buffer_;
   const int output_buffer_size_;
 
+  std::unique_ptr<I18nSourceStream> stream_;  // Must outlive `source_`.
   raw_ptr<net::MockSourceStream> source_;
-  std::unique_ptr<I18nSourceStream> stream_;
 
   TemplateReplacements replacements_;
 };