Alternative Spectre v1 using virtual methods and indirect jumps.
Alternative Spectre v1 using virtual methods and indirect jumps.

Works on all our platforms and compilers. On some it requires
compilation with -O2 or -O3. Can be mitigated either by retpolines
or by SLH.

Change-Id: I7a8bcaea7a735f7a78e362a429804adda763707e

google/safeside,google/safeside,google/safeside,google/safeside