RFR: 8290495: Micro-optimize Method::can_be_statically_bound assertions

[Aleksey Shipilev]

See the rationale in the bug.

The test time improves:


# Before
real 1m27.397s
user 2m39.937s
sys 0m5.966s

# After
real 1m13.443s ; -16%
user 2m24.238s ; -10%
sys 0m5.885s

-------------

Commit messages:
 - Fix

Changes: https://git.openjdk.org/jdk/pull/9548/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9548&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8290495
  Stats: 5 lines in 1 file changed: 0 ins; 1 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/9548.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9548/head:pull/9548

PR: https://git.openjdk.org/jdk/pull/9548