Disable File.getCanonicalPath caches.

File.getCanonicalPath has to always return accurate
results in all cases, not doing so has potential
security implications. Caches may have stale data
if underlaying files were modified by another process
or code that's not aware of cannonical path cache.

Test: vogar ojluni/src/main/java/java/io/FileSystem.java
Bug: 62301183
Change-Id: I76b0ca606405a958ebbc57a8a6c08deb53ea1dfc
(cherry picked from commit caed7373b2ed858c864a0c108cffd65d051534f7)
3 files changed