Fix blurry downscaled VectorDrawables

The original change was made because the cache could be shared
between two different views on screen at once. This is no
longer really possible thanks to commit
549ee05a so this workaround
is no longer needed, and now just causes quality loss.

Restore strict equality check for cache hits, which also
matches VectorDrawableCompat behavior.

Test: verified b/32780212 didn't regress
Fixes: 265838627
Change-Id: I5a01064f3fd8090238af6cde54ccb2cce1168bca