Intern class IDs. This way they compress better.

(cherry picked from commit 614bffcb316c36bdffd3d5d46b405e3721639e04)

Bug: 157638573
Test: Flash flame. Get heap graph.
Change-Id: I8ac3391394aa68cc0ca846e6ab34963c6ca313f4
Merged-In: I8ac3391394aa68cc0ca846e6ab34963c6ca313f4
1 file changed