Don't cross junction points when deleting old temp dirs (again).

https://crrev.com/784428 stopped recursing across junction points when
looking for CR_* or chrome_* directories. This CL does the same when
deleting within those directories.

BUG=1100280
R=forshaw@chromium.org

Change-Id: I7a4ef84d9df744cf5d0bd64d51065a571228520d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2292395Reviewed-by: James Forshaw <forshaw@chromium.org>
Commit-Queue: Greg Thompson <grt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#787752}

chrome/installer/mini_installer/mini_installer.cc

@@ -719,7 +719,8 @@ void RecursivelyDeleteDirectory(PathString* path) {
       if (!path->append(name))
         continue;  // Continue in spite of too long names.
 
-      if (find_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
+      if ((find_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) &&
+          !(find_data.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
         RecursivelyDeleteDirectory(path);
       } else {
         ::DeleteFile(path->get());